Unfortunately there is no native app could recover lost reminders directly on your devices, but you could recover reminders with a third-party iOS data recovery tool: iFonebox. It could help you extract and restore all of your reminders on your iPhone, iPad, iPod Touch, including the lost and deleted.
Free download the trail version of iFonebox, either Windows version or Mac version, and follow the tutorial below to recover your lost and deleted Reminders. (Take the Windows version as a example.)
How to Recover lost Reminders from iPhone, iPad, iPod Touch
Step 1: Choose “Recover from iOS Devices” as recovery mode
Install and run iFonebox, and connect your iPhone, iPad, iPod to computer with USB cable. Click the “Recover from iOS Devices” button.
Step 2: Start scanning your devices
After choosing the recovery mode, the software will automatically start the scan of your device. The progress bar shows the scanning process and the scan time depends on the number of your database.
Step 3: Preview and Recover lost Reminders
When the scan finishes, all of your data on your device including Camera Roll, Photo Stream, Contacts, Messages, Message Attachment, Call history, Calendar, Reminders, Notes, Voices Menos, Safari Bookmark is showed on the top of the interface. Click the “Reminders” to preview your lost reminders. Click the “Recover” button to recover them on your computer. Check the option before “Only display the deleted items” to only preview and recover the deleted and lost reminders.
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