Wireless Data Without Voice

[brianinottawa]

In the prepay world, it appears that to get wireless data service you need a voice plan that is hitched to a SIM. Is it possible to have your voice service provided by one provider and your data/Internet service provided by another?

Just wonderin'...

[andy]

only if it is a multiple identity SIM

some of the roaming SIMs are, but it's probably rather less likely with 2 providers in the same territory

and local SIMs are likely to have better data rates than roaming ones, especially for more than a little use

[brianinottawa]

I've never heard of a multiple identity SIM. Is it something that is available in all countries and on all GSM carriers/providers? If a provider/carrier does offer or claim to offer roaming, can one assume that their phones have multiple identity SIMs?

I have an iphone 3GS and I only need "seasonal" prepaid service. I would like to use a low-priced carrier for the voice side but (no surprise) they don't offer data. I'd like to subscribe to a month-month data plan or a prepay data plan from AT&T or TM or another GSM if one is available. Your thoughts???

[GadgetKen]

Think multiple ID sim is like the ekit simple calling sim card that has a UK and a US number assigned to it(Andy correct me if I'm wrong). Don't think would work well for an iphone though because while technically feasible, you wouldn't want to pay by the megabyte for data usage.
The iphone 3gs is a nice phone but is a bit of a data hog. It's possible to do AT&T prepaid with 100 mb data packs at $20/each...originally it was unlimited but some people got a bit overenthusiastic with data usage. Used to run an AT&T Tilt this way but I can't guarantee an iphone would work in the same fashion.
Some thoughts:
Get an ipad (I think they have moderately priced prepaid service packages)
Use a USB key on a MacBook. You can get month to month (I've got Millenicom/Verizon but they also represent Sprint and T-Mobile) or prepaid as you go...Sprint/Virgin Mobile is a nice value (varying packages up to $60/5 gb) and can stay dormant up to 1 year after last activation. AT&T and Verizon also have prepaid service now but it's a bit pricey compared to offers through resellers.
Unlock the iphone and use it on T-Mo with one of their no-contract options.

[GadgetKen]

Another thought...AT&T is coming out with new iphone plans to match the data plans for the ipad. Catch is these are postpaid and metered plans: AT&T's new data plans: What you need to know | Phones | iPhone Central | Macworld