Only 35 percent of Brits use the instant messaging (IM) function on their mobile phone, says ProcessOne.

Research by the instant messaging specialist revealed that while texting is a hugely popular method of communication, mobile phone users are becoming frustrated with its limitations.

Character restrictions was one of the biggest annoyances to handset owners, closely followed by 20 percent who dislike the lack of real-time conversation and the same percentage that lament the fact text messaging can't be used with a video function.

ProcessOne also highlighted that 60 percent of mobile phone users would be more likely to use IM than SMS if they knew how to operate IM functions on their handsets properly.

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"There is a great opportunity for mobile operators to educate their users about the benefits of mobile IM. With today's mobile devices consumers are wanting a much more real-time and interactive experience, in order to better communicate with friends and colleagues," said Mickaël Rémond, CEO of ProcessOne.

Two thirds of those surveyed said they would also use mobile IM more if their network operator provided them with a single IM service that would connect with contacts on other networks, while nearly half said they thought IM was too expensive.

"There definitely needs to be better clarity regards mobile IM pricing. It is apparent that people are willing to use services if they are priced correctly so there is plenty of room for mobile operators to develop innovative pricing options, whether it is a flat-rate fee or micro billing for add-on IM services, such as message histories or file downloads," added Rémond.

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