Can you use this without a sim on wifi only just for Instagram and Snapchat?

Why not?

​yes any phone will run its apps without the need for a SIM network .

These are used but may have minor marks on them. Each one has a separate description. E.g. Used with small marks on back. I have one but it has not been running as well as it did initially. This may be since the operating system(cyanogen) has stopped getting regular updates. Wileyfox say they are working on this but not much has happened since xmas.

Happens to all lower end android devices I find. Mix of cached stuff building up (my moto G4 was playing up, went to clear it as I hadnt done in awhile and was 4gb in size) and general bloat that happens over time due to poorly coded apps - sadly the only way to really get rid of it all is a factory reset and not restoring data/apps. Obviously more expensive phones mitigate this as when you have those 4gb RAM/64gb storage devices with fast processors its hard to saturate even with bloat.

iPhone won't.

​Another reason to switch to Android.

great price simply to use as a spare, mp3 player, sat nav etc...