Viber whatsapp faceboook app lagging

Hello,

I have been suffering from the viber,whatsapp,facebook app laggings. It take a approx 5~10 seconds to open these apps which is very very annoying. once the apps are open, next time it works normally. However after 30 mins or so, again same thing.

Iphone : 6plus

IOS : 10.3.3

Please help.

thanks