System becomes laggy after a couple of days?

[wps81]

My system was laggy today before I rebooted. The start screen is laggy and in-apps too. Animation no longer smooth. Rebooted and now it is fine. Never happend before upgrade. 1520

 

[Athull]

My system was laggy today before I rebooted. The start screen is laggy and in-apps too. Animation no longer smooth. Rebooted and now it is fine. Never happend before upgrade. 1520

Until the firmware update comes from Nokia such lags are to be expected.