I have been using Duolingo exclusively on my iPad for the past year, at one point had a streak of 155 days going. Within the last month or so I started having significant problems using my iPad for Duolingo lessons, the app ALWAYS crashing when I tried to start a lesson, sometimes 4-5 times before I could actually begin a lesson. I tried a lesson this morning, made two mistakes, lost my "health" and could either pay you or wait 4 + hours. I would have given up but instead brought up the program on my PC a short time later, where my "health" did not seem to be an issue. I completed my daily expectation, not without errors, but was allowed to finish. Just wanted to let someone know that as I spend long hours working on my PC, being able to use my iPad for something fun was valuable to me. These problems with the iPad app have diminished the value of your program to me.
My ipad has had some problems with the app lately too. Some of the lessons wouldnt open. I too only use my ipad for lessons on the bus and at home (as i dont really use my home PC after being at work all day). I hate the new mistake health thing, and the change from Lingots to whatever the new point system is not near equal. It takes much longer to earn the points and costs much more points to save your daily streak (not that I have used it but i like having that option as I am at a 113 days). I like to be able to redo the lessons over and over from the beginning and if i make a mistake i cant always utilize all the time i have to redo lessons and make it really sink in, and i too found it fun. The changes to the app make me more anxious and not want to use it.