In most cases, those things aren’t likely to be a problem, since Apple has been careful to keep everything important hidden.But if you’re particularly worried, then it’s worth having a look at every widget in the unlocked view and removing any that you’re worried about.
Twyxt's calendar was the runner-up, but still didn't sync with Google Calendar or i Cal so it didn't beat Between.
This also had a "List" ability, a "Kiss" feature (similar to Couple's "Thumbkiss") and messaging system.
Avocado used to be one of the highest rated apps amongst couples, but if you see the recent reviews, users are not happy. I reached out to Avocado support but did not receive a response. While the app offers picture sharing and a chat section we wouldn't use, its calendar was the easiest out of all of the apps..some flaws: It doesn't sync with Google Calendar or i Cal.
The app has not been updated since July of last year, most likely the cause of the issues. I used this app in a previous LDR (sorry, babe) and liked it.
Again, those things might mostly be useful – but if you’re especially worried or at risk of people trying to mess with your phone, it might be worth turning them off.