How can I receive offline (via text messages) flight status alerts or subscribe my relatives?

Go to the Flight Feed → Open Flight Alerts widget. This is where you can subscribe to the text alerts for yourself or others.

You need to set this up for each upcoming flight.

iOS

Select Subscribe (you can also do it via View button → "Add Subscriber")

You can select a person from the contacts or enter manually. Or choose any recent subscribers.

Also, you can set up alert types:

• Follower – all updates, including delays, gate changes, and status changes
• Family – only take-off and landing notifications
• Attendant - only departure updates
• Welcomer - only arrival updates.

Enter the phone number in the international format (starting from the "+" sign). Here is the list of codes by the country: https://countrycode.org/

Android

Select configure (or if there are alerts "X More")

Tap Settings bookmark

Tap the "+" sign

Enter a person's credentials. 

The phone number should be in the international format (starting from the + sign). Here is the list of codes by the country: https://countrycode.org/

Also, you can set up alert types:

• Follower – all updates, including delays, gate changes, and status changes
• Family – only take-off and landing notifications
• Attendant – only departure updates
• Welcomer – only arrival updates.