GreatCall Jitterbug $86.28 Bringing back the clamshell in a big way, the Jitterbug keeps it simple with YES and NO buttons and big numbers. You can add their 5Star Urgent Response system to speak to a live agent who can help with your situation or figure out your location. It's even endorsed by John Walsh!
Snapfon ezONE-C Senior Cell Phone $59.99 You want big buttons? You got it. You want fewer buttons? Done. There's not much to this phone, which keeps it as simple as possible for ease of use. A simple lock/unlock switch on the side prevents accidental dialing without having to teach the grandparents the concept of "swipe to unlock" or swiping a complex pattern. Works with AT&T and T-Mobile.
JUST5 J509 Personal Emergency Response System $67.00 Big red buttons and a speaker phone. What else does grandma need? It's unlocked, so just pop in an AT&T or T-Mobile SIM and you're good to go. The JUST5 pone is compatible with hearing aids, and there is a programmable SOS button. Plus red means emergency, right!
SpareOne Emergency Phone $52.00 The SpareOne is small, and best of all, it runs off of a single traditional AA battery with a talk time of 10 hours and a 15 year shelf life. Not as small and simple as the other models, but the battery options makes it easy for the grandparents to recharge it.
MORE EMERGENCY PREPAREDNESS ON APARTMENT THERAPY: • 911 Emergency Calls In A Modern Wireless World: Truths & Tips • Displaying Lists, Notes & Emergency Info at Home (Images: as linked above)