I love that it allows you access through many different providers, including those with limited data plans like T-Mobile or Comcast in my situation (no more having an unlimited plan).
Also great if there are no free minutes left during billing cycle which can limit usage of service while waiting until next month's bill comes out! Great way too keep costs low with only paying what needs be paid instead using expensive monthly subscriptions at other carriers when not needed just because one does have them as part their phone contract/billing agreement; this helps immensely since these services aren't always necessary all day every single moment so sometimes its nice being able do use without needing constant payment throughout entire time period required by carrier subscription agreements!!