New iPad mini 4 just over 3 hour battery life?

Hi,

My son has just used his savings to upgrade his iPad mini 1 to an iPad mini 4 as he was getting frustrated with a lot of his games no longer working due to iOS 11 not being supported. We would have gone for a 3 (that’s what I have) but couldn’t find it for love nor money, so the 4 it was.

We have always had specific rules in place regarding charging, in order to keep battery life as it should be. These are:

1) No charging until battery drops below 10%

2) No playing with it on charge

3) Once on charge, it stays on charge until it reaches 100%

Pretty straightforward and on the whole the kids are pretty good at following these rules. Imagine my surprise then when I realised how quickly the new iPad was runnning out. Today was particularly bad - so I had a look at the information and saw that the time since last charge was around 3 hours 15 mins in use and 6 hours or so on standby. Nowhere remotely near the 10 hours boasted by Apple!

I have just been through the settings changing the brightness, removing notifications and location services where not needed, deleting apps unused, etc. The only things he has been using it for are playing ROBLOX and watching You Tube Kids.

The iPad was bought brand new from Amazon but a third party seller. It is the 256gb version if that makes difference, it was in the proper box and all sealed up as expected.

Does anyone think we may just be unlucky and have a “duff” battery? Or is this typical of the iPad mini 4? Any suggestions for improving battery life would be appreciated so that I can get it lasting longer for him - I should not be having to charge it anywhere near as often as I am for him!

Many thanks in advance. Chelle.

Edit: I forgot to say, he’s running the most up to date version of iOS.