The inReach will check for new messages according to the message check interval that you set. You can make adjustments to the message check interval at anytime on the Earthmate app. Follow these steps to adjust the message check interval:

1. Open the Earthmate app 

2. Tap on More.

3. Tap on Options.

4. Tap on Messages.

5. Tap on Check Interval.

6. Select from one of the following intervals:

• Off (you must check manually each time)
• Continous (constantly checks network)
• 2 minutes
• 5 minutes
• 10 minutes
• 15 minutes
• 20 minutes

If you select the "Off" option you will need to check for new messages manually each time. Instructions for initiating a mailbox check can be found here: http://support.inreachcanada.com/kb/articles/148.