Agreed. I have lost challenges because the whole problem doesn't display on the screen at once especially when the keyboard is up on the screen. Having a full size monitor and keyboard would really help with challenges. I wish you could have a longer set time to do the math as well.
we need chalenges in web version, looks like you prefer apps because they are more wealthy for ads and rating in googleplay, you can also add ads to web version and make money from the website ranking, am i right??
Please bring challenges to the web! Or, make a desktop app. It doesn't make all that much sense to code on a mobile device because nobody codes like that in real life. So the only way I'm going to do challenges is on the desktop, and for that to happen please make either a desktop app, or a web challenges feature!