One in five BlackBerry phone users is considering switching to another supplier because of the service problems which hit millions of people last week, according to a study. A survey of more than 1,000 BlackBerry customers by shopping comparison website Kelkoo found that 19 per cent are thinking about moving to another manufacturer. Meanwhile, 42 percent will consider changing later and eight percent said they have bought a new mobile phone already. Kelkoo said that with today’s launch of the iPhone 4S already boasting pre-orders of over one million, this week’s service issues could not have come at a worse time for BlackBerry, giving users a “tempting ship to jump to”. Research among another 3,000 people found that seven out of 10 who were planning to get a BlackBerry in the future admitted they would need some reassurance from the manufacturer as they would be put off by the recent problems. Four out of five consumers said they were put off choosing a handset from a manufacturer that has experienced major service problems.