Where Offline Synced Google Docs Are Stored on macOS

Google Docs has full view and edit functionality on the iPad (see here and here). To be honest though, it's kind of like trying to chop down a tree with a plastic spoon. It feels quite clumsy, it's fairly slow and it's not something you'd want to be a regular part of your work flow.

You're unable to select text, which means no copy or pasting. If you double-tap at the end of a sentence to get a period, you won't be rewarded with that particular mobile shortcut. There is no shift key; if you capitalize a word, all the text will be capitalized until you toggle the button off. Backspacing is equally slow, especially if you need to edit a large area of text. Tuaw

There are Apps like GoDocs that claim to make the experience better, but I haven't tried them myself.

If you don't have an iPad (and I'm presuming you haven't because you're asking this question!) you can get your Mac or PC to pretend to be an iPad in Safari and try it out yourself. Fire up Safari's preferences and tick the show develop menu under the Advanced Tab:

Then use the Develop Menu in your Menu Bar to set your User Agent to Mobile Safari 3.2.2 - iPad. Your browser will act just like it was an iPad, which lets you experience with Google Docs or any other sites you're curious about.

I can suggest several for title editing, but I'm unaware of any that offer headings.

If you've already scanned through the available App Store offerings without much success, then I can suggest little-else. It's not about a hack, as Google hasn't gone out of their way to restrict you in this fashion. Probably on the long list of to-do's.