New user here on free version. How long are the receipts  and reports kept for in the back office? Is there a limit or are they there indefinitely? ie will they still be there next year when I go to do my accounts? 

Also I know there is a list of recommended printers for receipts but can they be printed off on an air printer or just those listed? Don't want to have to buy another gadget if I don't have to!

hello

receipts are stored in the back office without restrictions
you can see the paid features on the website https://loyverse.com/pricing

 

about printers 

for Android, you can try to connect to models that are not on the Supported Printers list. But be aware that not every printer may work with Loyverse POS

https://help.loyverse.com/help/how-set-other-printers-loyverse-pos