You can secure your secrecy and precious memories for yourself.

Secret Calculator... will help you lockdown your secret photos, contacts, passwords, and private browser
An iPhone calculator that works, exactly like any other calculator until you type in your secret passcode. The calculator then turns into a private storage place where you can hide all your most secret photos, videos, notes, files, contacts and more.

Disclaimer:
Secret Calculator... does not keep your photos or datas in any kind of servers. It uses the internal storage of your device only. If you delete the app, your photos & datas saved in the app will also be deleted. So make sure to export your photos, videos from the app to your device's photos gallery if you need to delete the app for any reason!