“Use git. Install Working Copy and Textastic apps. iA Writer is good too. Turn Photos and your editors to work with Working Copy. Push changes to your server repository. Enjoy productivity on iOS."
When I bought my first iPad, I was morally prepared that this Thing is not for work. I was right, it was not good. Not even for writing text. Nor for managing servers neither for maintaining PHP application code. Three hardware generations later I can say now - “It is good enough for those kind of things”. What iOS software made it possible to finally do something useful on iPad?
Firstly, its git. You really should save your texts and programs in decentralised repository, making them virtually indestructible and manageable, by which I mean easily syncronised files across all your devices and apps, easily comparable, not to forget versioning, which is git all about. Could be GitHub account, or git installation on your own server.
Secondly, its git client on iOS. I have not tried all of them. What worked for me is Working Copy app, written by Anders Borum. It is a full-featured git client. It allows to save your stuff from other iOS apps as long as they support the iCloud picker, that was introduced in iOS 8. That feature means my first iPad is useless, but my iPad 3.1 can become a working horse.
Thirdly, the code or text editor. Textastic is my iOS code editor of choice, and I found iA Writer app to be extremely handy for Markdown and texts. Both are easily configured to save to and load from Working Copy interface to your git repositories.
Edit your text, and it will be added to repo by Working Copy. Push to server from WC and your words achieves a certain degree of immortality, since it is tricky to actually delete something once commited to git repo. You can diff in WC. The only quirk in the UI is that you have to “Open in...” in order to “Save in Working Copy”. Do not be afraid of that and stay creative.