Religious jews do not control electrical appliances on many jewish holidays, including alarm clocks. Many also pray starting at different times in morning, depending on the day of the calendar.
Yes, I intend for the app to always be free ב"ה. Apple hosts it for free under a non-profit account so that we can provide it for free. At some point, I might offer the ability to donate to my local shul. For now, you can express your appreciation financially only via the KAJ website.
Maybe. It can't hurt to ask.
I don't have a great solution. Here are some alternatives:
turn off haptics for your phone entirely
configure haptics to be off in silent mode, and then turn on silent mode before shabbes, and off after shabbes (perhaps configure toggling silent with triple back tap)
Perhaps configure your phone to use 24-hour time?