It's nothing to do with your phone or tablet - there seems to be a problem with both the iphone and android versions of the app itself. There have been a number of posts about it on the tech board.
E.T.A I've just seen this thread on the Tech board
I won't hold my breath that the app can be sorted out, but hope it might be possible to provide a mobile version of the site? (Unless they already do and I just can't figure out how to access it!)
Thanks for info. I use this app a lot, so I'm a bit sad it's not working. It was easy to use, I liked it. And to use site via chrome or any other internet browser is not so comfortable I admit. But, oh well, I guess I have just to get used to that.