R7000: Smartphones connect to WiFi and can navigate using browsers, but no Internet with Apps

Hi to all,

      I have just installed my new R7000 WiFi router and I am experiencing some strange issues.

My WiFi configuration consists of two WiFi networks, one on the 2.4 GHz frequency and one on the 5 GHz frequency.

I have connected with success my two smartphones to both these networks. The strange thing is that if I use any browsers I am able to navigate, while if I launch apps like Google Play, Facebook and LinkedIn they are unable to obtain access to Internet.

I have the latest firmware installed (V1.0.6.28_1.1.83) and already tried an hard reset and re-configuration.

Has this thing happened to anybody??

Thank you in advance