Sure! You can use it whenever you'd like someone to call you but not for them to have your real phone number. Why not get a number mask before you go out for the evening? That way, if you meet someone you like, you can give them your number but it won't be your 'real' one until you get to know them a bit better and want them to have it.

It's also an incentive for them to call you within the time span you set ... a real case of use it or lose it!
Another use - say someone wants to call you but they don't want to have your (identifiable) number on their phone bill? No problem - get a number mask and all that will appear on their bill is an 070 number that will have elapsed after whatever time span you chose.

Disclaimer:
Please note if you use the number for fraudulent use, the Police or authorities will contact us for the number routing, we will corporate fully with the authories, helping them crack down on crime.