Decide the best way to shoot
This is a simple tip that's all about preference. Aiming can be tricky to control sometimes so it's good to experiment and see which finger to best use when aiming. Using your thumb is convenient if you want a more one-handed experience. Maybe you have something in your other hand so this might work out well for you.
Of course, it's all about comfortability, so maybe you rather use your thumb anyway. If you're more of a two-handed player, then you can try using your index finger for aiming too. It's all just preferences.
Feel free to experiment with both to see which helps you aim better. Remember, it can be tricky to get it just right when presented with awkward angles. So give both styles a try, or come up with something totally different. Whatever helps you best destroy those orbs.
Aim more horizontally
Ahh, yes, if you played some classic games in the past, then you'll be familiar with this strategy in Orbital. Depending on where the orbs formed, I'd highly recommend aiming your shots more to the side. Let the shot bounce off of the wall and watch it hit the target.
If you decide to aim too high, then, your shot will likely drop down and hit the death line. If you go for a more horizontal shot, then it should bounce off of the top of one of the orbs. This will cause the ball to stop and form a new orb for you to destroy.
You'll be able to hit more orbs in succession by utilizing this strategy. Now, sometimes if your shot starts to head towards the death line, it might stop right near and for an orb. So if you have no choice but to shoot more upwards, just hope that your ball does drop below that line.
Try to get multiple orbs close together
This is easier said than done, but getting orbs formed right next to each other is a great way to take them out faster. Try using the horizontal tactic we talked about, and have the ball bounce off the top orbs. You normally can get in a couple of knocks on each one at the same time.
Remember, you need three hits to destroy one orb. By doing this, you should be able to knock down one of them by letting the ball bounce a couple of times. Then this should leave the other one with a shot or two left away from destruction.
It's always beautiful when you can string a bit of a combo together. This is certainly one way to do it if you play your cards right. Just keep in mind that another orb will form where your shot lands. If that's near the top of the orbs you're trying to destroy, then that might close the opening.
If that's the case, then just keep trying to utilize the horizontal approach. Attacks the orbs from the side.