I'm guessing because of what's mentioned here: https://news.ycombinator.com/item?id=31491321 https://news.ycombinator.com/item?id=31491321 TLDR: Their Calendar

I'm guessing because of what's mentioned here: https://news.ycombinator.com/item?id=31491321 https://news.ycombinator.com/item?id=31491321 TLDR: Their Calendar app became "not free" and you needed to pay to get notifications or alerts, but only if you downloaded from the Play Store. It's still completely free on f-droid