I bought a MiFi5510L Jetpack at a local Sacto shop with "prepaid" plan (it was $75). The reason was to enable temporary network access for family visiting at my Mom's for a few weeks. There are online plans for like $15/60/90 for 250M/3G/10G for one month - but can I also buy the "Wireless Data AddOn Cards" (at CVS and WalMart etc.) to add data in smaller increments like $10/20/30 ... ?? It is unclear if and which prepaid cards may work with it (or how to use them).
Thanks for any info.