Is it carbonated? If it's carbonated, you can store it at cellar temps if you wish. If it's not carbed up yet, keep it in the 68-70 degree range until it is.
Cider-y flavors might get better, but might not. Usually, high temperatures cause hot alcohol flavors, not so much cidery flavors. Cidery flavors come from young beer, and maybe some beers that don't have much malt and use other things like sugar for the fermentables. Either way, aging it might improve it quite a bit!