iPhone 4 cannot connect to internet via wifi

My iPhone 4 is unable to connect to the internet via wifi. This was working for me earlier today, but has stopped working. I can connect to the wireless network, but when I try to access internet functions (eg use safari) it does not respond. I have an iPad that is able to connect to the internet using the same network.

I have tried several suggestions that I found on support pages:

• Chose 'forget this network' and re-entered network password
• Reset all network settings via Settings->General
• Switched my iPhone off and on again using sleep/wake button
• Reset my wireless router
• Performed a soft reset of my iPhone (holding round sleep button on sleep/wake button on top)

ios is version 7.1.2

Can anyone offer further advice?