You can sync Todo for Mac with Todo (iPhone or iPod touch) and Todo for iPad by following the steps below:

• Prepare your network
  • Your iPhone must be connected (Wi-Fi) to the same router your computer is connected to.
  • All your network components (firewalls, routers, anti-virus) must allow communication from Appigo Sync and Bonjour.
  • Turn off your device's (iPhone, iPod touch or iPad) Bluetooth connection. This is only needed for the initial pairing process.

• Pair Todo for Mac with your iPhone, iPad or iPod touch
  • Optional but recommended step: Back up all your iCal calendars before you sync for the first time. 
  • Open Todo for Mac and go to Todo > Preferences > Synchronization
  • Select 'Local Network Sync' and click 'Continue'

  • Click the '+' button and follow the prompts

• Initial Sync
• Once you are done with the pairing process, Todo (on your iPhone or iPad) will display your sync options.
• Exit out of these options and all the other settings
• Tap the sync button

• Subsequent syncs
  • Simply tap the sync button in Todo (on your iPhone or iPad)
  • This will trigger a 2-way sync between Todo for Mac and Todo