my iphone 6 working slowly on ios 9.1

my iphone 6 on ios 8.3 last version of ios 8 was working fine. But when i upgraded it on ios 9.1 and restored my previous backup data to ios 9.1 my phone working slowly than ios 8.3 even i clear my all multitasking windows / apps and restart than same apps which i cleared they shown ....

i just dont want to lost my messages any solution.?????????