Truphone has officially launched a business client for the BlackBerry that will allow users to make cheaper calls to international numbers.

Once the Truphone Business app is installed on the handset, users simply dial an international number as usual. However, once the call button is pressed Truphone intercepts the call and routes it over the internet. Callers only pay the cost of the call to Truphone, which is charged at local rates.

Truphone launched the beta version for Blackberry users back in October last year.

The app is free to download, but users must take out a subscription with Truphone to access the service. TruStandard costs £2.50 ($3.56) per month and offers call charges of 5p per minute, while the £5-per-month TruSaver package offers prices starting from 3p per minute.

Geraldine Wilson, CEO of Truphone, said: "Truphone Business is extremely compelling, particularly in this economic climate. Companies are keen to cut costs but find that an increasingly mobile and global workforce need to make international calls from mobile devices as a part of day-to-day business. Truphone solves that problem by providing international calls from mobiles at fixed line rates."