user26591: I'm working on a proof-of-concept for a blockchain project and at its core it will need a modified SPV node running on iOS. The reason I need to modify it is so I can build non-standard (e.g. OP_RETURN) scripts without seat-of-the-pants techniques like hacking into the transaction hex.
I'm aware of some basic starting points such as picocoin and libbitcoin which I should be able to compile for iOS. But is there anything else available that would specifically make an SPV node easier to develop on iOS?

user2306: There are Objective-C libraries for Bitcoin, like CoreBitcoin, but none of them implement an SPV client.
My thinking (I've never developed for iOS, only for android) is that you should use a mature solution, like BitcoinJ, and a tool like J2ObjC to convert it. I think that would give you a faster (in terms of development time) and better-tested solution.

user26591: I have found this iOS SPV client library: https://github.com/keeshux/BitcoinSPV

user26682: BreadWallet for iOS is open source, has a permissive license, and uses SPV https://github.com/voisine/breadwallet/blob/78d67870cdb887bab69ffeab8d808a3cb24d3759/BreadWallet/BRPeer.m

26591: <p>I'm working on a proof-of-concept for a blockchain project and at its core it will need a modified SPV node running on iOS. The reason I need to modify it is so I can build non-standard (e.g. OP_RETURN) scripts without seat-of-the-pants techniques like hacking into the transaction hex.</p>

<p>I'm aware of some basic starting points such as picocoin and libbitcoin which I should be able to compile for iOS. But is there anything else available that would specifically make an SPV node easier to develop on iOS?</p>
 2306: <p>There are Objective-C libraries for Bitcoin, like <a href="https://github.com/oleganza/CoreBitcoin" rel="nofollow">CoreBitcoin</a>, but none of them implement an SPV client.</p>

<p>My thinking (I've never developed for iOS, only for android) is that you should use a mature solution, like <a href="https://github.com/bitcoinj/bitcoinj" rel="nofollow">BitcoinJ</a>, and a tool like <a href="http://j2objc.org/" rel="nofollow">J2ObjC</a> to convert it. I think that would give you a faster (in terms of development time) and better-tested solution.</p>
 26591: <p>I have found this iOS SPV client library: <a href="https://github.com/keeshux/BitcoinSPV" rel="nofollow">https://github.com/keeshux/BitcoinSPV</a></p>
 26682: <p>BreadWallet for iOS is open source, has a permissive license, and uses SPV <a href="https://github.com/voisine/breadwallet/blob/78d67870cdb887bab69ffeab8d808a3cb24d3759/BreadWallet/BRPeer.m" rel="nofollow">https://github.com/voisine/breadwallet/blob/78d67870cdb887bab69ffeab8d808a3cb24d3759/BreadWallet/BRPeer.m</a></p>
