In reply to Erik B: Hi, I am the App developer.
The data does come from the met office data point service. The met office do encourage the use of this for app development which is a really healthy thing. MWUK focuses on the mountain oriented data feeds and presents them in an organised and visually appealing manner.
I felt it only right to include the MWIS and SAIS links as these are essential services that everyone uses. The only impact in my opinion will be to direct more traffic to MWIS and SAIS, which is a good thing for everyone.
I have spent the last year putting this app together in my spare time. I hope everyone really likes it.