I have two pieces of advice for iOS users: Back up your device and check out iFoneMate. The software s built to recover lost, deleted or damaged data from pretty much any iOS device.
When the program is installed on a Mac or Windows computer, it examines a connected device to find missing data. It looks for photos, notes, contacts, calendar entries, voice memos, deleted messages, WhatsApp data and Safari bookmarks. It can recover data detected directly from the device or stored through backups using iCloud or iTunes.
The Windows version of iFoneMate costs $49.95 and works with Windows XP, Vista, and versions 7, 8 and 8.1. The Mac version costs $55.95 and works with OS X versions 10.6 through 10.10.
More details are available at the iFoneMate website.