Felons who can verify their low-income status (usually with proof of government assistance such as food stamps or medicaid) can order free cell phones from any of the resources at the bottom of the page.
Every government phone provider should guarantee you at least 250 minutes/texts per month, but many are offering special incentives like 500 minutes for the first 4 months and unlimited texts for as long as you use their service.
We can’t say which is the best, but it costs you nothing to shop around or even try one at a time until you find a carrier you are happy with.
Also, make sure to check with your parole/probation officer about any restrictions such as no camera or no internet. The basic phones (without internet and cameras) are more difficult to find and you will want to ask the provider about the features on the particular phone they are sending you.