The thermometer did not work for 1.5" steaks, but I probably used it wrong and will try again.  It worked perfectly for a tri-tip.

It seems that the app needs to be used in a particular sequence.  Backing up in that sequence seems to erase what was done previously.  It will take some time to get used to the sequences.

It worked well with my Apple Watch, too.  Very convenient to check cooking progress on my wrist instead of carrying the phone.  This product is far better than opening the lid to insert an instant read thermometer.