what's a cheap cell phone used just in case of emergency for an elderly person?

You can get a prepaid cellphone pretty cheap these days, like $25. You can buy a small number of minutes, like 30 min., and then just hold onto them for emergencies. In fact I think the phone comes with 30 min.

You just have to keep the phone charged. Sounds simple, but it's a bigger hassle to keep a phone charged that you never use!

Check your local Wal-Mart and Radio Shack and Best Buy.

get a prepaid phone (flip phone) with a company that offers voice only plans. Usually you can get one for 5-10 dollars a month