ASDA Mobile is a virtual network which means that it relies on another provider for the network and hardware it uses. ASDA is based on EE. If you want to know what the signal is like around you area, please go ahead and check out the ASDA Mobile coverage map which will give you a good indication of what the coverage is like.
ASDA Mobile is run by the supermarket of the same name. As you would expect, it markets itself as a cheaper alternative to the other mobile networks. It was one of the first virtual networks in the UK to offer significantly lower prices on the PAYG model. Since then it has massively increased its prices but it still remains easily one of the best-value options available. ASDA Mobile even offers cheap monthly bundles for texts and calls which can help you save even more money. As they use the EE network, they are the bestchoice for decent UK coverage.