How to preserve fruits for 10+ months?

It depends on what equipment you have and what flavour compromises you're willing to make, each preservation method will have its own downsides.

• Freezing will give you good results, but you better make sure you vacuum pack the fruits to protect from freezer burn (might be counter productive if you have to re-seal it every day, or expensive if you use multiple bags). You can also use resealable bags, of course, but there will be some ice formation in the long run.
• you could dry the fruits if you have a food dehydrator, but you'll need to re-hydrate the fruits before making a smoothie. Or use them dried but it might not have a nice texture.
• canning could be a good option, provided you already have the equipment + canning jars. It will also change the flavour of the fruits.

I also drink smoothies on a regular basis, and I use two different methods:

For bananas I usually buy them unripe (it gets less bruised as I bring it home) then once it's just ripe I chop it and freeze it in a resealable plastic bag. It's easy enough to get just the amount of fruit I need and I'm not too bothered with freezer burn, since I consume it fast enough.

For berries I thought about also buying it for cheap when in peak season and freezing it myself, but I just buy the frozen version from the supermarket. Why?

1. it's cheaper when buying big bags
2. they're picked already ripe, so they are as tasty as they can
3. they're usually flash-frozen, so less freezer burn. I can't flash freeze at home with a conventional freezer
4. I can buy them any time of the year

For your apples you might consider chopping before freezing, and some people recommend pureeing (also bananas). I personally believe it's better to break down the fruit the least possible, so less of the fruit gets exposed to oxygen and subjected to oxidation (which will cause browning and change of flavours).