The National Blood Service has found a way to get blood out of a phone.
A trial at five universities found that sending text messages to students increased donor levels by 32 per cent.
The NBS decided to target students who were willing to donate blood but hard to track down because of their mobile lifestyles.
Trials were carried out at the universities of Kent, Brighton, Kingston and Surrey using mobile numbers collected at freshers' fairs.
The scheme will be expanded into an initiative to increase attendance at donation sessions at 25 universities and colleges in London and the Southeast. If all goes well, it will be used nationwide from September.