Kotlin libraries

[OmegaStarScream]

What are some good resources for android (java/kotlin) developers to start making bitcoin (or crypto) apps?

I know there's Wallet-core (made by Trustwallet) and bitcoin-kmp[2] (made by ACINQ). Anything else would you like to recommend?

[1] https://github.com/trustwallet/wallet-core
[2] https://github.com/ACINQ/bitcoin-kmp

[NotATether]

There also seems to be BitcoinKit for Android 6+ that implements an SPV implementation, if you need any of that. But it mistakenly says its an iOS project in the description. Useful if trying to make an Android wallet (though it also supports Bitcoin Cash).

[PawGo]

What are some good resources for android (java/kotlin) developers to start making bitcoin (or crypto) apps?

I do not know how it is with kotlin, but for java you may easily use both bitcoin core libraries if you want to work on btc and org.web3j library if you want to go in that direction. The rest depends on you but basic things like wallet/address creation, private key verifications etc - all is easy to do.

Code:

        <dependency>
            <groupId>org.bitcoinj</groupId>
            <artifactId>bitcoinj-core</artifactId>
            <version>0.16.1</version>
        </dependency>
        <dependency>
            <groupId>org.web3j</groupId>
            <artifactId>core</artifactId>
            <version>5.0.0</version>
        </dependency>

[ABCbits]

Since you say "java/kotlin", AFAIK BitcoinJ is best option out there. It's been developed since early 2011[1] and used by several wallet such as "Bitcoin Wallet" for Android[2] and even forked by Bitcoin sidechain Rootstock[3].

[1] https://bitcointalk.org/index.php?topic=4236.0
[2] https://play.google.com/store/apps/details?id=de.schildbach.wallet
[3] https://github.com/rsksmart/bitcoinj-thin