After looking into this a little more, Amazon's DRM does not require wifi at all. Once you purchase the app, the Amazon DRM does an initial check to make sure the download is legit, and that's it. Sorry for the confusion - didn't mean to make you worry.
Yes, I would always advise using the Google Play Store if possible. You will get updates the fastest, and it allows you to submit error reports which really help me fix things faster.
Yes, I would always advise using the Google Play Store if possible. You will get updates the fastest, and it allows you to submit error reports which really help me fix things faster.