BE AWARE!
TelCel has many plans. From cheap to noteworthy. A month to month MONTHLY plan is not a contract. And it is a heck of a lot cheaper than a fixed price plan that lasts 60 days. I am graduating to a 500 peso/month plan that allows 5+ gigabytes internet and many hours USA call time and unlimited Mexico time. WhatsApp is a very popular application down here. When there are no modems and no cafes a cellular is the only access possible*. In rural area, cell internet may be slow but I use it 2-4 AM if really necessary.
*I need it for banking and for cardiac medicines.