Here the pic reminders will play important role to store your all pictures of event on particular date wise.
You can also set reminders for each event to remind you on specific date which can be your anniversary, birthday, any future event, repeat seminars, etc.
The only difference is the pic reminder will remind you with visual form of memory instead of just texts.
You can take backup of your whole app on your favorite cloud Google drive and dropbox. In case of loss of your device, you can simply restore your backup from cloud where you have stored to retrieve your images and events with reminders