These devices will allow you access to calls, Texting and a small amount of data.
The SatSleeve range can access data at up to 60kbps down and 15kbps up. This is best effort and allows checking of simple sites like Bureau of Meteorology Text only forecasts etc. Accessing net banking or other high level sights is not recommended.
The Iridium GO gives you access to calls, Texting and VERY limited Data. The raw data speed is 2.4kbps which is about 20 time slower than the old dial-up. Really only recommended for text only Iridium emails and downloading yacht weather Grib files.