I’ve been working on a 3D bowling game in Unity lately. It’s going pretty good! I feel the UI definitely could be better. Seeing as there are about 5 different sliders to modify properties…
But the list of features:
-Good pin physics (Modified their rigidbodies idk how many times to get the best results!)
-Sound effects for hitting pins and rolling ball, also bowling alley ambience sound, gutter effect coming soon
-Nice bowling alley mesh I got on opengameart (Thanks to FuzzyQuils for helping me import with texture!! 
)
-Curve, sidespin, throw angle, and power slider UI’s. That’s what I feel could be optimized for easier use.
-Automatic pin-resetting. Strike detection works for the most part. Or 2 balls.
-Hardly any bugs with performance.
-Kinda addictive! Oh wait this isn’t a feature lol sorry XD
I think that’s all I got.
I haven’t bowled for many many years but isn’t curve dependent on the amount of spin on the ball & the traction it gets on the alley, particularly in that last bit where there isn’t as much oil? If you could split the alley & redoing it so it isn’t noticeable you could have low friction on the first bit & higher friction on the last bit.
As for power sliders & angles, most throwing style games I’ve played tend to do power based on holding the mouse down & angle is again controlled by the mouse. This could be down angry birds style by having the player pull the ball back for power & move it around for the angle (this would work for touch screen as well since those games are doing fine on the App Store). Controlling spin could be a bit more difficult but the Kinect version of bowling had the spin dependent on bringing your arm across as you bowled, perhaps you could try linking it to a similar motion on screen?
Thanks for your reply! As for the oil, I would like to ask for clarification on what you mean. There is one lane part the ball moves on. It has a physics material when it moves that has 0 friction. Then when the ball is at the appropriate distance from ‘DistancePart’ the physics material is removed and any curve added to the ball then reacts like real bowling.
Good idea with the power thing. Although a partial newb with Unity still, I bet I can get that to happen. Like the mouse being the angle. And holding down the mouse button to generate power. I will work on these features ASAP! Hopefully I can get them up and running quickly too. But how to determine curve. That’s a hard one… I might just leave the slider up for now. But further suggestions would help very much!
Thanks again! 
Your way with the physics material works. I was suggesting having 2 parts but just turning it off once the ball reaches a certain distance from the start of the lane has the same effect.
For curve you could perhaps track mouse movement in one direction after the ball is released for a fraction of a second only? Not sure I this will give enough control for the amount of variance in spin, but I’m also not sure how much control good bowlers have over the amount of spin the impart on the ball either.
Interesting. I will try some stuff like this. Thanks ted!
Consider using tilt controls to curve the ball like in the Android game Bowling King
Note that making too many sliders can clutter the screen and confuse people.
Why not show what you’re working on so we have an idea?
I’ve kinda been out of it for awhile now. But for now the controls are all on the mouse. You hold down the mouse button to charge up power and curve, and then the ball goes to where your mouse is pointing. You can also drag the ball to move it.
Aaah, I thought you were going for mobile (Android, iOS, Windows phone)
Oh, I’m not gonna do that yet. Still need more experience.