If you have a child in Reception class, or in a pre-school playgroup then this Free App might be very useful for helping your children with their reading skills. It's available for Android for free at Amazon right now.
Most schools now use the phonics based system of teaching, and around 80% use the Oxford Reading Tree System to teach reading. If your child's school is one of these then you will find that the characters, concepts and sounds on the app are familiar to them, so you can use it at home to reinforce what your children are learning in school.
My son is now in Year 1 and he used some of the Biff, Chip and Kipper activity books in the long school holidays, and if the app had been free at the time I would have downloaded that too. As kids are always asking for phones and tablets to play games then this one will be teaching them at the same time.
Only the Level 1 app is free, with the next reading levels costing £1.49 each at the moment, but it's a good idea to try this one first and see if it suits, even if your child is reading at a higher level.