Subscriptions to General Motors’ OnStar system are set to soar to 7.9 million by the end of 2017 from 5.1 million in 2010, according IHS iSuppli.

The research company said the rise will mirror sales growth for GM as a whole. Sales of OnStar in new GM cars, where the service is bundled into the vehicle, are expected to grow to 3.2 million by 2017 from 2.1 million in 2010.

In addition, iSuppli expects renewal rates for the service to grow to 60 pc this year and remain at that level in coming years.

The OnStar telematics services is included free of charge for a year in all new GM vehicles in North America. In subsequent years, the automaker charges a subscription fee for the service, which includes automatic collision notification, stolen vehicle assistance, on-board navigation and other features.

OnStar recently announced that it would start selling this summer a 299 dlr aftermarket module that would make the service available for non-GM brands as well. The OnStar mirror will be sold through the Best Buy chain of consumer electronics storeis.

iSuppli said the move would open up “huge potential for more sales of the service.”

OnStar is available in North America and China. The wholly owned GM division is studying whether it will start selling the service in other countries.