I disagree that it is a great summary. Yes, an eraser would add another mode and that is a good point but that is where the greatness stops.
1. Firstly, glhaynes posted this comment after my edit (can no one see my edit!?). That means glhaynes posted a comment on a comment that I had retracted without acknowledging that. Why?
2. and the app is free
You can still sell something that is free.
3. Simplicity can be difficult to achieve. I would argue that your app, would be simpler to use if it had an undo button. If I sketch a face and completely ruin it with one errant line, it is simpler for me to tap undo than to start from scratch. How is an undo button adding any more complexity than clear or save?
4. And, if you're gonna have all that, why not also allow various thicknesses of the drawing tool? And colors?
Why have save, clear, share, print, copy or mail? I would argue that adding an eraser can be done in a way where that is extremely intuitive, certainly a lot more intuitive than double tapping a grabber.
5. The only reasons for not having an eraser or undo in this case (simplicity is not a reason in this case as the ux is already complex) is that it is a feature of the app to not be able to hide mistakes or change what has been done (`I agree that this is similar to sketching on paper) or some misguided use of skeuomorphism. The summary fails to go into this.
So That is why I disagree that it is a great summary.
You seem upset that I didn't note your retraction, as if I'd done it maliciously. That's not the case. Isn't the more straightforward explanation that you made your edit during the time it took me to compose my reply?
I am sorry, I acted like a complete idiot throughout this entire thread.
To clarify, I had no problem with your post. It riled me up when the OP endorsed it while some of it was not valid (at the time of their post) but I responded in a ridiculous manner so please forget about the whole thing.
Thanks a lot. I do consider pull to save the primary action. Double tap or shake gives you the menu, but I agree this can be simpler. It would pain me to put instructions in the app though...
++ on the pull. What could help though is to display something transient-ish while you are "flipping the page" (to not present the direct modal choice, but to give a hint there's more). I am a relative noob in iOS coding, so not sure how easy it is.
The "real" problem that I perceived is the double-tap, and I have debugged my interaction a bit more.
What it looks like is that the triple-equal sign is a bit too small for my fat fingers. OTOH you do not want to waste the drawing space too much...
My thought would be: take a rectangle of 2x size the current triple-equal sign action area, then try to both use the drawing mechanism there, as well as to track the doubleclick-like events there - and if one happens, then undo the last drawing event (which was a part of the click, anyway).
I think this should make it easier for fatfingered people to deal with it :) And the translucent advertisement upon the swipe should take care of education, I think.
Thanks for offering solutions. It can be improved I agree. We had thought about some one off instructions like this and perhaps that's something we'll think about.