Help choosing how to replace a couple apps

I've recently switched to Android from using a BlackBerry for the last 10 years. I'm having trouble with a couple functions I depended on before that don't exist anymore now after the switch. The stock "tasks" app doesn't set the reminder to the next date on recurring tasks. Just the due date. So I need a replacement app. And the stock "calendar" won't let me delete a single instance of a recurring appointment without also deleting every instance after the one I'm deleting. So I need a better calendar too. The obvious choice would be the official Google calendar, but I don't want any online access or syncing. I need it all to only exist locally on the phone. My budget's approximately $25/year for both. Suggestions on what might be suitable?