Recommend me a basic tablet for AIS

my favourite charting app was the raster ipad timezero tz-iboat https://mytimezero.com/tz-iboat

Out of interest, what are the "in app purchase" costs (charts and I presume the ads overlay)? Maxsea always looks lovely but the cost is frightening.

Unfortunately I'm something of a fan of paper charts and only recently acquired an iPad but some other random thoughts for the op:
* You don't generally need the iPad with a sim card. The sim card slot on a new iPad will set you back £130 (40% of the cost of the basic model). A garmin glo bluetooth gps will set you back £86.43 inc delivery and integrate into the apple location service. You can also use it with your laptop and some apps can take GPS from NMEA wifi data anyway. The glo's battery did not last all the way round the island this year though.
* "How do I convert NMEA-0183 to wifi?" has been discussed *lots* of times before here :-)
* No personal experience of it but if you already have navionics on iOS, digital yacht's iAIS app on apparently has an in-app purchase enabling overlay of AIS on navionics charts you already own. Review and comment on other ais display options on this guy's blog:
http://i-marineapps.blogspot.com/p/top-5-best-marine-ais-display-apps.html
* The difference between the free vs paid opencpn is 3 years and support
 
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