To mine 1 ethereum coin using the gpu of a 500$ nvidia GTX1080 graphics card it takes 2 months. The gtx1080 can crunch 2 roughly 25.000.000 hashes per second.

Sure, there are ethereum miners for android (look for minergate on google play).

Ethereum has been designed to make it impossible (at least… none succeded until now) to be mined using specialized hardware chips designed explicitly for the mining task, so the graphics card GPU miner, for ethereum is still the most powerful miner you can get.

For bitcoin this is not true: GPUs are outperformed (the same way a gpu outperforms a phone) by dedicated ASIC miners which are a thousand times faster than GPUs.

Now: both coins have in common that they automatically get more hard to be mined to compensate the introduction of more powerful hardware: there is a predetermined number of coins to be generated globally every day: you just get a slice of this pie and its size is proportional to the amount of computing power you can offer compared to the total amount provided by the rest of the world.

Miners are in a continuos competition one against the other in getting the most powerful hardware they can and the cheapest electricity bill.

Today it is practically impossible to mine bitcoins without using ASIC miners: it takes months to get one bitcoin using an ASIC miner, it takes decades using a GPU and well… a phone is as useful as a stone for mining bitcoin.

Moreover: keeping an ASIC miner running, today has electricity costs high enough to make it more convenient to simply buy bitcoins at the regular markst price, unless you live in a place where electricity costs are really low (read: China)… or unless you get your miner powered by solar panels. But you need hundreds of asic miners to get some serious money, today, and they aren't cheap.

Bankers and industry leaders in the Texas panhandle have recently been discussing what to do about blockchain technology and bitcoin. They are curious how they can get banks involved in leveraging cryptocurrencies, because they do not want to be left in the dust. However, some of them are also scared for the banking industry. In their eyes, bitcoin has the power to undermine the banking system and reshape the financial landscape.
To Fear or Not to Fear Bitcoin; Average Nerds on the Street Versus Bankers

Another banker at the Amarillo National Bank does not harbor the same fears. He recognizes the future potential of digital currency, though. Vice president Stewart Dodson of Amarillo Nation Bank said the dark, shady roots of bitcoin will be a deterrent for future adoption. He said bitcoin’s past use to facilitate dark web transactions have tainted the currency’s appeal. Now it will harbor that stigma forever.Banker: 'I am Scared for the Banking Industry...Bitcoin could Knock Banks out of the Game'

Even though Dodson sees bitcoin as tainted, he admitted a “digital currency” will eventually be adopted by the mainstream. He mentioned various payment apps like Venmo and Applepay could win the race, even though they are not cryptocurrency-based platforms.

Jon Laur, chief technology officer for EnergyNet — an Amarillo-based oil and gas auction and sealed bid transaction service also chimed in on the discussion. He said banks need to get ahead of the game. He mentioned that if banks do not have someone on the payroll who knows more about cryptocurrency than “your average nerd on the street,” they will be left behind.

Future of the Banking Industry

In the final analysis, the bankers concluded digital automation could change the face of the industry. The convenience of digital currencies makes jobs expendable, and could replace some banking roles. The article detailed, “In a region with 6,600 financial sector employees as of 2014, according to the Texas Workforce Commission, lower-level positions could be eliminated or simply not added as banks invest more in Internet services.”

By destroying I will define as a take a bitcoin (an entire unit) and destroy it. In theory the action of destroy is possible.

Use an invalid address with no private key: Just send bitcoins to an invalid address. For example: Bitcoin Address 1CounterpartyXXXXXXXXXXXXXXXUWLpVr
Use bitcoins to send data (notary document ownership or some ID). See Why New Forms of Spam Could Bloat Bitcoin's Block Chain
In theory, you’re not destroying bitcoins but in practice, you’re almost burning these bitcoins.

No one knows for sure (with any degree of certainty). Having said that, most agree the future is bright. That statement does have a few caveats. The following is my prediction:

Bitcoin itself as a protocol will evolve. Many people forget the simple fact that it is a protocol first and the money part just happens to be the first app written over it. Think of it like the Netscape browser written for (predominantly) HTTP. It was good at its time, but then other browsers took the mantle and Netscape was dethroned. The same analogy could apply to bitcoins (the money). It could be dethroned and for all we know Dogecoin or  Litecoin could prevail.

The Buying process of Bitcoins will have to be made much more simpler than it is at present. All indications point that the process will get more streamlined, so buying bitcoins will be an easy task.

In most countries (US included), companies that trade Bitcoins onto the local currency would be regulated. More exchange companies will mushroom.

Acceptance. Until and unless Buyers keep pressing / asking Merchant to accept Bitcoins, merchants will be oblivious to the demand. If you walk into a store and ask if they accept Bitcoins and they answer No, this is the expected answer. Repeat this scenario with 10 other Buyers asking the same and the Merchant will think differently. They just might start looking at Bitcoin acceptance.

Much of the developed world where payment systems that enable instantaneous person-to-person payment are not available, would love to adopt Bitcoin. The barriers are the regulators and the almost near vacuum of local Bitcoin exchanges. Look at India - no exchange in India. Same can be said of Pakistan, Bangladesh, GCC, Indonesia, Philippines, Thailand (though there are a few players in Thailand who are selling Bitcoins), North Africa, etc. There is a very large population that simply does not have access to buying bitcoins. Since they cannot buy it - they cannot trade with it. This will be changing in the coming months/years.

Volatility will minimize. I won't say it will disappear, the public at large is too sensitive to everything the media spews out relating to Bitcoins.
Arbitrage will almost be negligible.

You will see the movement pickup speed with a few authoritative anchor users accepting Bitcoins. (See  this excellent article by our resident Payments Maestro Brian Roemmele - Starbucks To Accept Bitcoin In 2014. by Brian Roemmele on Accepting Payments).

As more and more larger corporations start offering Bitcoin as a payment alternative, many companies waiting in the shadows will jump onto the bandwagon. This chain-reaction trigger is very important for Bitcoin to survive. Many are waiting for the trigger.

I don't think the price for the next 2-3 years will break $5,000 (the expectation of it going to $25,000 to $500,00 - will be bad for Bitcoins in my opinion, too many speculative money will enter the ecosystem, which will cause regulators to clamp down hard on Bitcoin). My personal estimation is that it will hover between $1,000 to $2,500 (for the next 24 months at least).

Acceptance of Bitcoin as an alt. currency in developing countries would be very important (as opposed to outright banning it). I however, have my reservations on this. The regulators in the developing have a very myopic vision when it comes to alternative currencies. Such obtuse undertaking will kill Bitcoin (in a legal manner) in the developing world.

The market capitalization indicates in some manner that the currency is now too big to collapse (not that it cannot happen), by a measure of its own self, it will most likely survive.

Bitcoin will be featured regularly in the Remittance World (a sure sign of its success would be the World Bank reporting remittance figures on the Bitcoin platform) - How this will be done, is debatable and questionable, but I'm leaning in as a proponent.

Snap Payments with Bitcoins for Websites, Freelancers, etc. would be enabled. This means, very quickly accepting $25 in Bitcoins, which are in turn converted to Euros and available in your pre-paid Debit Card (all by inserting some simple code on your website to accept the payment). Think BitPay or Coinbase on steroids, globally.

Currency Brokers will be trading and dealing with Bitcoins more regularly.
Bitcoin exchanges in the West (perhaps US, or UK) will prosper and take over in volume (provided international clients are allowed to hop in and trade).

Incorporation of Bitcoin payments within Social Media would be the norm. You would definitely see native or plug-in based activity around Bitcoin. Think Twitter, Pinterest, Facebook, LinkedIn, etc.
Apps not related to money, but related to the open-ledger system of the Bitcoin protocol will start emerging. I'm absolutely lost when it comes to giving such examples, but I am sure, someone out there is thinking of a kick-ass way of using the Bitcoin protocol and building a non-payment app on top of it.

Currencies based on the Bitcoin protocol or modified protocol, will start seeing a market themselves for specific purposes. It could very well be that Litecoin might dominate the Remittance market, or changing Linden Dollars to Litecoin. Or Mastercoin is used on boards like Warrior Forum or Digital Point (the Affiliate Marketing Ecosystem) or Peercoin is what is most accepted and traded in South Asia or South America. Such patterns and/or segmentation may very well emerge.

The future of finance could be dominated by blockchain technologies. A traceable global currency complete with an efficient infrastructure will not only result in massive cost reduction for all market participants, it will change global banking. Bitcoin will do for payments what email did for communication.

What is changing?
Blockchain will be adopted by central banks and cryptographically secured currencies will become widely used.
Nasdaq will launch blockchain-enabled digital ledger technology that will be used to expand and enhance the equity management capabilities offered by its Nasdaq Private Market platform.
The settlement of currency, equity and fixed income trades almost instantaneously through permissioned distributed ledgers creates a significant opportunity for banks to drive efficiency and potentially create new asset classes.

Control

New technologies such as blockchain have the potential to reduce cyber risks by offering identity authentication through a visible ledger.
There is no reason why requirements for numbering, maintaining and indexing records and communicating information provided in records could not be met through an electronic ledger system.
Car rental agencies could use smart contracts that automatically allow rentals when payment's received and insurance information is confirmed through a blockchain record.
A refrigerator equipped with sensors and connected to the Internet could use blockchain to manage automated interactions with the external world-anything from ordering and paying for food to arranging for its own software upgrades and tracking its warranty.
Small businesses could use blockchain to create trusted trading platforms among themselves.
Blockchain could potentially help bring robustness and transparency to the post-trade environment.
New technologies such as blockchain have the potential to reduce cyber risks by offering identity authentication through a visible ledger.
A bank could pay the supplier instantly over the Internet.
Blockchain technology will alter timing on risk.

Crime

A new blockchain startup has claimed its software could help track down criminals faster and cheaper than ever.
Connecticut are warning parents that a new Darknet cryptocurrency called Bitcoin could be to blame for helping underage drinkers to get buzzed.

Implications

Banks

Blockchain will be adopted by central banks and cryptographically secured currencies will become widely used.
Blockchain could replace central banks.
Real risks remain for banks that choose to get involved with cryptocurrency firms.
Blockchain technology could reduce the UBS's infrastructure costs in cross-border payments, securities trading and regulatory compliance by as much as $20 billion a year by 2022.
The number of applications within and outside the banks could be reduced as the Blockchain transaction contains all relevant information for the successful transfer of assets and/or related contracts.
Deutsche bank's economist sees blockchain as a threat because of the lack of the IT infrastructure to support the technology involved.
Ethereum is much more general purpose than bitcoin and could be useful for banks.
The future of finance in many nations could be dominated by Bitcoin and cryptocurrencies.
A private blockchain run by banks could end up as just "another cartel" and function as poorly as the payments consortium.
Banks could become the "custodians of cryptographic keys".
The blockchain could save lenders up to $20 billion annually in settlement.
Blockchain technology could be used to bypass today's centralised financial infrastructure entirely.

Industries

Time and education will need to play a role as other industries are just realizing one of the core innovations of the blockchain is its ability to reduce or eliminate trusted counterparties in the transaction process.
Blockchain has the potential to create new industry opportunities and disrupt existing technologies and processes.
Blockchain technology will make the world even smaller as it increases the speed and efficiency of transactional activity.

Governments

The future of finance in many nations could be dominated by Bitcoin and cryptocurrencies.
Blockchain technology could be used to distribute social welfare in developing nations.
Elections are currently an expensive and arduous. Thanks to blockchain tech they will soon be instantaneous.

There is one type of attack that could affect the bitcoin network: the 51 percent attack, which is widely considered to be bitcoin’s greatest inherent flaw. Because it is decentralized, bitcoin is vulnerable if any one player or cartel gains control of 51 percent of the computing power of all miners. This would allow them to stop transactions and reverse transactions, which would throw the network into chaos. In the past, at least one group has achieved control of 50 percent of the network. However, the more people using bitcoin, the safer it is — and more people are using bitcoin now than ever. It’s difficult to get an accurate count of how many users bitcoin has, but the estimates are in the millions.
Where Bitcoin becomes truly insecure is when other technology starts to get involved. Bitcoin was conceived as a “trustless” system; you don’t have to trust any centralized party in order to use your money, because transactions are facilitated by other members of the network. In reality, bitcoin is too complicated for most people to use without mediators such as apps, wallets, and other digital currency services. The biggest need is for third party exchanges, which are sites where bitcoin is bought and sold for other currencies. All these third party services are only as safe as their own security. Mt. Gox, arguably the most famous example of an exchange going belly up, filed for bankruptcy in early 2014 after around 850,000 bitcoins went missing.
Bitcoin is still largely unregulated, which means your money isn’t insured and there is often no accountability for exchanges. So while bitcoin tech itself remains unhacked, the methods used to collect, buy, and sell remain as potential attack vectors.

I Think the possibility is very high, but it is still a long time before bitcoin can overcome paypal, we still need to increase the user amount, and not all people in the world know bitcoin, but most of the people in the world know paypal. But it will happen soon.

Bitcoin has grown considerably in popularity over the past several months, with prices almost tripling and more and more cryptocurrency followers joining the field. As this has taken place, so too have the number of publicized hacking events increased as well. With more money being invested in digital currencies now than ever before, and particularly given that many investors are new to the system and may not know how to keep their investments secure, hackers are coming up with ingenious ways of stealing funds. Some of the most prominent thefts have been those that have taken place in plain sight: a recent hack rerouted tokens bound for one wallet for another. The victims watched as their tokens were stolen away from them, with nothing they could do about it. Here are a few ways to store your Bitcoins that may be safer than others.

Desktop Wallet
A desktop wallet offers a number of advantages over an online wallet. While online wallets are easily accessed from anywhere in the world, they are also more vulnerable to potential hacking. Desktop wallets, on the other hand, are accessed only via your private computer, with personal security keys stored just on that machine. Thus, exposure of your security key online is reduced. Nonetheless, desktop wallets are still susceptible to hacks if your machine gets infected with malware designed to root out keys and steal Bitcoins.

Hardware Wallet
More secure than a desktop wallet is a hardware wallet. These wallets are bits of hardware, external devices like USB sticks which you can carry around on your person. An added benefit of a hardware wallet is the complete anonymity with which you can transact. There is no personal information linked to the hardware, so no identifying data which could be leaked. Hardware wallets are resilient to malware, and if you happen to lose the wallet you'll be able to recover the funds using a seed phrase.

Paper Wallet
A paper wallet is also a relatively safe way of storing Bitcoin, although it requires a bit more advanced understanding of how digital currencies work. Generate a paper wallet online using any number of dedicated websites, or generate the wallet offline for even greater security. Paper wallets are stored easily because they don't take up a great deal of space, and they also offer true anonymity: they are simply a Bitcoin seed written in some way on a piece of paper.

Physical Coins
Services are cropping up which allow Bitcoin investors to buy physical Bitcoins. The coin you purchase will have a tamper-proof sticker covering a predetermined amount of Bitcoin. In order to purchase the physical coin, you may need to pay a slight premium over the value of the Bitcoin that you're buying, owing to the cost of the manufacture and shipment of the coin itself.

In India, Its not fully deployed but ICICI bank is the first bank who complete its first banking transaction using Blockchain technology in partnership with EMIRATES NBD and a lender from West Asia.

Blockchain technology allows for the secure management of a public ledger or database, where database transactions are verified and securely stored on a network and is managed by a network of nodes that all have their own copy of the database.

When the 1st block of transaction is created, it is marked with a HASH FUNCTION.

Blockchain also provides you a secure WALLET where you can store your bitcoins safely.

ICICI is now the first bank in this emerging technology who participated while many online retailers already accept BTC, some major companies still plan to or already have adopted this new currency like Amazon, OKCupid and Western Union.

Can i claim bitcoin gold after the fork ?

What should a zebpay user do. Are they supporting it, will one get bitcoin gold if he will keep his btc on zebpay during the hard fork ?

Yes, he said that bitcoin is unstoppable. I saw that video on YouTube. It is a big thing. I don't know he invested in it or not but surely he supported it. Which build more trust in people.

What are the exchanges that would support bitcoin gold and what are the ways to get bitcoin gold?

yes it is always risky to invest all your money in bitcoin. Its very volatile. So invest as much amount so that you would have some money if something would happen to this market.

A Bitcoin ATM allows users to buy and sell Bitcoins for cash.
Bitcoin ATM’s can be more expensive than online transactions as the infrastructure cost is higher – i.e. building an actual ATM and the steps that are actually needed to transfer the money and Bitcoins.
The first step is to scan her identification which the ATM then validates.
Then the user feeds in some cash and generates a QR code from her wallet – a QR code being a large square of black and white pixels. Then the user sends the Bitcoins to the presented address.
Some ATM’s generate a paper wallet – or offline wallet – essentially a bearer instrument of the Bitcoins.

No central bank or governmental authority backs the safety or soundness of digital currencies. Unlike fiat currencies like the US dollar, which is printed by the Federal Reserve, bitcoins are minted by complex interactions across a broad global computer network.

Due to the nature of digital mining, bitcoin’s value cannot be manipulated or altered. Bitcoin's value is secured thanks to the cryptographic functions that it employs, and though it could be hacked one day in the future, technology and cryptography experts agree that such an attack is unlikely in the near-term. However, the networks and storage locations where bitcoins are housed and “protected” can be hacked by malevolent forces. Despite assurances by bitcoin storage companies and developers of the currency, bitcoin exchanges can and have been hacked.

There are three prominent hacking cases of bitcoin exchanges in recent years:

Bitstamp: The Slovenia-based Bitstamp exchange represented the third-busiest marketplace for bitcoin at the beginning of 2015. The exchange processed roughly 6% of bitcoin transactions. The firm announced a breach in early January 2015 and shut down its services temporarily. When the smoke cleared, thieves had taken off with roughly 19,000 bitcoins (BTC), a fraction of the exchange’s total assets. Rather than keep its assets on live exchanges, Bitstamp had stored more of the currency on local hard drives, a process known as “cold storage.” The total heist was valued at $5.1 million.

Mt. Gox: The most prominent bitcoin hacking occurred in 2014. Mt. Gox, which was based in Japan, was once the largest marketplace for bitcoin, and processed roughly 80% of all global transactions for the currency. That was until a security breach at led to the heist of $460 million. The hacking soon fueled a price collapse of the cryptocurrency, with bitcoin falling by half in less than a year. Following the well-publicized heist and blow to bitcoin, Mt. Gox confirmed that it faced roughly 150,000 hack attacks every single second. Just one of these attacks made if possible for thieves to make off with 750,000 bitcoins and bring the exchange to its knees.

Bitcoinica: Before there was the collapse of Mt. Gox, there was the fall of Bitcoinica. Bitcoinica was hacked in March 2012, and had lost a large share of coins. Despite the bad press and the attack, the firm promised to pay back users in full for their losses and improve security. Unfortunately, neither happened. The company was hacked a second time just two months later and shuttered its website. The company said it would then repay users for 50% of their previous holdings.

This too would prove impossible. While Bitcoinica attempted to reboot, it built its entire business around Mt. Gox. However, legal proceedings were brought against the exchange, forcing Bitcoinica to let all of its holdings sit idle in Mt. Gox exchanges while the courts attempted to sort out the second case ever involving digital currencies. While lawyers bickered, Mt. Gox was hacked, and anyone who still had Bitcoinica accounts proceeded to lose anything that was left.

These aren’t the only hacking attacks in recent years. Hackers took down the zloty and euro exchanges of Polish exchange Bitcurex last March. The firm lost “between 10 and 20%” of its funds. That same month, Canadian bitcoins announced it lost $100,000 after a hacker breached vulnerabilities in the exchange’s security protocols. And Picostocks, a bitcoin stock exchange, also lost 6000 BTC in 2013, despite having just four clients trading on it. Bitcoin wallet services BIPS and Inputs.io have also reported breaches in recent years.

Yes, ofcourse bitcoin is changing the world in many aspects.

“The future of money,” “drug dealer’s dream,” “transformative,” “disruptive”– Bitcoin has been called many things. Beyond its anonymous nature, bitcoin has the potential to change the way we bank, make transactions, and view money.
A rare combination of technology and finance with global reach, bitcoin’s framework is impressive. Its real potential is not in its high exchange rate valuation or in providing an additional virtual currency that is free from governmental or political interference. Bitcoin’s potential lies in its underlying technology, a secure system with built-in authentication of transactions and record keeping, which could change the global financial ecosystem.

There is always risk in investing whole of your money. Btc price may go down then what would you do...
Always keep some amount in your hand so if prices will go down you won't be backholder.

Bitcoin Uses
1) Spending Money Privately
One of the biggest pros of bitcoin is its pseudonymous quality (members are identified by the public keys rather than their “real world” identities). For many people, this affords a desired level of privacy that traditional digital payment systems do not. Some examples of situations in which this quality really comes into play include situations in which people are fleeing from abusive partners, desiring controversial health procedures, or operating outside the confines of oppressive governments.

Unfortunately, there is also the flip-side of this privacy; capability for bitcoin to be used for unethical and criminal purposes. The most infamous example of this is Silk Road – the massive “Deep Web” marketplace. Silk Road used the privacy inherent in bitcoin (as well as an anonymizing software called TOR) to allow for users to buy and sell contraband. While the moderators of Silk Road didn’t allow for the sale of goods resulting from or intended to cause the harm or exploitation of other people, users could still illegally purchase contraband such as illicit drugs and forged identity documents. Bitcoin’s relative anonymity could also potentially provide criminals with avenues for money laundering or funding terrorist organizations.

2) Low-Cost Money Transfers
One of the biggest pros of bitcoin is that, compared to other electronic payment systems, it has a very low transaction cost. Bitcoin’s transaction fee is not nearly as costly as the fees on money transfers brokered by banks, credit cards, and commercial software like PayPal.

3) Online Casinos
One popular destination for many Bitcoin users is online casinos where you can make fast transactions and wager as many coins as you want. If you’re a more experienced Bitcoin user, you can even track all of the bets you’ve placed through the block chain.

Most major operators offer Bitcoin as an alternative to more traditional currencies, though there are now numerous online casinos that deal solely in Bitcoin. To ease the learning curve for new users, these brands often partner with sites like BitcoinPokies, who aim to teach you everything you need to know about betting with Bitcoin.

3) Online Shopping
In December 2014, Microsoft added Bitcoin to their list of payment options on their Windows platforms and X Box gaming consoles. This allows US based patrons to exchange Bitcoin for money in their accounts so they can purchase games, videos, apps and more.
As Bitcoin grew in popularity, other merchants like Dell, Overstock, Cheap Air and TigerDirect began to accept Bitcoin as a form of payment. Now, you can buy gift cards for major retailers including Walmart, Amazon, Target and Nike from a number of companies like Gyft that trade Bitcoin for credit.

4) Restaurants & Hotels
These days, even travel companies are allowing Bitcoin on board. Last year, Expedia teamed up with Coinbase to add Bitcoin to their list of accepted payment methods, making it the most famous travel company to accept the digital currency.

As for bars and restaurants, there aren’t very many that recognize Bitcoin as payment right now. However, Bitcoin.travel has a comprehensive list of all accommodation, attractions, bars and restaurants in the world that do. So, if you’re interested in swapping your Bitcoins for a beer, just look up your local pub and check to see if they are accepted.