No not like blockchain.info. Inputs.io is an off-chain wallet meaning you are trusting the site with your coins. With blockchain.info you are responsible for your coins and the site owners have no access to them.
This is a common myth. Blockchain.info has multiple ways to access your coins:
1) Serve you a bugged JS file
2) Store your password when you use the API
3) Provide you with incorrect transaction data for double spending attacks
If blockchain.info (or someone with access to Blockchain.info) wanted to take your coins, they have a high success rate. It's a hybrid wallet, not a offline one that you compile from source.
1) You can compare the JS with what is on their github repo. Better yet use their browser extension.
2) Don't use their API or use a different wallet if you want API access.
3) Yep this is possible but you can just as easily double check transaction data on blockexplorer.com
The big difference between inputs.io and bci is that bci does not run a lending operation that offers extremely high interest rates.
A lot of people start off with online wallets. But it is better to move to a desktop client once you've got the hang of things.