A computer-savvy grandmother could change the face of education after her revolutionary idea was turned into an Iphone app.

Mary Coen, 60, a teacher at St Elphege's School in Wallington, has developed new software for the PC with children at her school.

To improve handwriting, Mrs Coen, with the help of her husband John, came up with the prototype for an iPhone app based on the programme.

Now the app, ABC Joined Up, has been picked up in America where schools have snapped up copies.

It is an interactive programme in which youngsters can draw the outlines of joined up letters onto their phone and then trace over them. Mrs Coen, believes it will improve parent involvement with education at home, and change attitudes to handwriting.

The teacher has 20 years of experience in schools and 11 as a literacy co-ordinator for the borough, where she goes in to school to improve handwriting proficiency.

She said: "Parents can see their children do this at home ensuring they are forming letters correctly.

The app will correct them if they are not drawing letters the right way. They will be able to see their development in their hand patterns."

The soon to be retired teacher said: "Handwriting is really important for children's literary skills. Unless they learn correctly early, they will be forever playing catch up. There is a lot of evidence to suggest that they will be left behind."

Ian Toone, from The Voice teaching union, said the app was a great idea.

He said: "It is important children continue to use handwriting. I'm concerned that computers are taking over, although there is a place for them in education. A lot of psychological research shows handwriting can improve speed of thought and creativity."

The application is available on iPhone and the iPad, comes with an American or English voice-over and has a step by step guide for users.