I have been developing IOS apps for some time. I have used or learned many open source libraries during the development process and shared them here.
1. tbxml (available on GitHub or the official website)
Tbxml is an XML library based on Dom parsing, which is very convenient to use. I have written an XML to dictionary tool Class Based on tbxml. If you need it, contact me.
2. sbjson (available on GitHub)
Currently, HTTP Communication in many projects uses JSON communication. Sbjson is an industry-recognized objective-C implementation version of JSON format.
3. sfhfkeychainutils (available on GitHub)
Currently, many applications store sensitive information by name or encryption/Decryption. In fact, cocoa touch has used a secure keychain for us to store sensitive information, however, cocoa touch interfaces are too difficult to use, so sfhfkeychainutils is available.
3. asihttprequest (available on GitHub or the official website)
Asihttprequest is an HTTP framework that can be used to solve all aspects of HTTP. I have read that asihttprequest is basically used for HTTP related IOS projects. I'm not sure it's not because asihttprequest is too easy to use. Anyway, I'm sure the nsurlconnection provided by cocoa touch is too difficult to use.
4. mbprogresshud
Mbprogresshud is a modal progress bar. It is essential for the UI during asynchronous requests and prompts a loading or something.
5. Facebook SDK for iOS
I won't explain the famous Facebook. It's useful anyway.
6. regexkitlite
Regexkitlite is a very useful regular expression library. I don't know how Apple doesn't even provide a regular expression framework, but regexkitlite is very useful.
7. ziparchive
Ziparchive is a very useful zip compression & decompression framework, which is often used for packaging, uploading, or data synchronization.
8. egoimageloading (GitHub)
Asynchronously load controls for images
9. egotableviewpullrefresh (GitHub)
Many applications now provide the drop-down refresh list function.
10. ctmbase64