Here is one of the thinnest smart food thermometers money can buy. The CHEF iQ Smart Thermometer comes with sensors accurate to 1F. It combines with your smartphone to let you monitor cooking from anywhere. You can also access guided cooking recipes on your phone.
These smart thermometers last up to 40 hours on battery. You can add 2 probes for large parties. The base has a built-in speaker to help you keep up with alerts. More information is available here.