I've noticed that after going into an area that doesn't have signal (my local supermarket) I get no signal which is fair enough. However as soon as I step back outside it continues to say "no signal" even after a good few minutes being outside. The only way I can fix it is by turning my cellular data on and off, or restarting my phone. I don't think it's a network issue, my friends has the exact same phone, white iPhone 5 and same network. Both on Orange but his seems to work after being in a no signal area. Does anyone have any ideas on how I can fix this, it's so annoying.