Just thought I'd share some results from the geosim (hassle free sims) test that we've been running.
We have had the SIM in a roadster on AT&T network in USA, for the past two weeks. Between 27th September and 11th October (15 days), we were billed a total of US$1.39 for data and US$2.95 for SMS. The data was billed at 1.36MB.
- The SMS charges were for 6 international SMS messages sent by the module on 27th September (kludgy setup with some mis-steps). With my new web-based sms provisioning system that would have been US$0.00.
- Assuming half the month, the full month data charge would be US$1.39x2 = US$2.78/month, for around 2.72MB. We estimate around 60KB a day (1.8MB/month), so this is a little higher, but the mobile providers round-up connections to the nearest 10KB, so this is to be expected.
- Yearly, the charges for this SIM should be US$0.00 to setup (or if you do it locally, perhaps US$2.00), then US$33.36 + US$10.00 yearly fee = US$43.36/year.
- With our new adaptive reporting code in the latest firmware, I'm seeing my data usage go down to about 1/6th. 60KB/day has gone down to <10KB/day. Now, the mobile providers round-up so in poor cellular coverage areas that is not going to be as good, but I think we'll see at least 50% savings.
- Overall, this seems pretty good to me. We lose SMS control, but the SIM and service itself seems fine. Hopefully the web-based provisioning system should simplify that.
We're going to continue the test with v1.5.1 firmware (should be released tomorrow), to see how well the new adaptive reporting algorithms translate to actual usage with the cellular providers rounding up connections to 10KB.
Regards, Mark.