Some applications lose their data when I update them. What steps can I take to ensure this doesn't happen to me when updating Todo?

• Back up your iPhone or iPod touch by performing a full sync with iTunes before installing any application updates.
• Disconnect your iPhone or iPod touch and install the update using the App Store on the device.
• Run the updated software on your device.
• If you did not lose any data, then you are finished.
• If you did lose your data, you can restore it from the iTunes backup.
• If you just reconnect and sync though, you'll lose your backup data too because iTunes will overwrite it with the current data (which was lost). So, to prevent that, you need to do the following:

• Disable automatic syncing in iTunes for your iPhone or iPod touch before re-connecting your device.
• You can do this by going into iTunes Preferences... > Devices and check Prevent iPods and iPhones from syncing automatically
• Connect your iPhone or iPod touch and wait until it appears in iTunes.
• Right-click (or hold down control and click) on the iPhone or iPod touch and select Restore from Backup...
• This will start a restore which will return your device to the state it was in before installing the updated application.

NOTE: If you synchronize with Appigo Sync, Toodledo or Remember The Milk, restoring your task data is simple; just set up synchronization again in Todo and synchronize.