Why my leantween animation works in Unity editor but not on my Android device

Some candidate ideas:

  • there may be a device-only error happening (check the logs)

  • it might be working but ambiguously mis-layered and the layers sort slightly different on device (if using sprites)

  • it might be working but mis-anchored / mis-scaled (if using UI)

  • some other timing issue might be at play (A script that depends on another running first)

Whatever it is, here is an approach to figure out what’s going on:

You must find a way to get the information you need in order to reason about what the problem is.

What is often happening in these cases is one of the following:

  • the code you think is executing is not actually executing at all
  • the code is executing far EARLIER or LATER than you think
  • the code is executing far LESS OFTEN than you think
  • the code is executing far MORE OFTEN than you think
  • the code is executing on another GameObject than you think it is
  • you’re getting an error or warning and you haven’t noticed it in the console window

To help gain more insight into your problem, I recommend liberally sprinkling Debug.Log() statements through your code to display information in realtime.

Doing this should help you answer these types of questions:

  • is this code even running? which parts are running? how often does it run? what order does it run in?
  • what are the values of the variables involved? Are they initialized? Are the values reasonable?
  • are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

Knowing this information will help you reason about the behavior you are seeing.

If your problem would benefit from in-scene or in-game visualization, Debug.DrawRay() or Debug.DrawLine() can help you visualize things like rays (used in raycasting) or distances.

You can also call Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene manually, looking for all the parts, where they are, what scripts are on them, etc.

You can also call GameObject.CreatePrimitive() to emplace debug-marker-ish objects in the scene at runtime.

You could also just display various important quantities in UI Text elements to watch them change as you play the game.

If you are running a mobile device you can also view the console output. Google for how on your particular mobile target, such as this answer or iOS: How To - Capturing Device Logs on iOS or this answer for Android: How To - Capturing Device Logs on Android

Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

Here’s an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

If it is layering:

Three (3) ways that Unity draws / stacks / sorts / layers / overlays stuff:

In short,

  1. The default 3D Renderers draw stuff according to Z depth - distance from camera.

  2. SpriteRenderers draw according to their Sorting Layer and Sorting Depth properties

  3. UI Canvas Renderers draw in linear transform sequence, like a stack of papers

If you find that you need to mix and match items using these different ways of rendering, and have them appear in ways they are not initially designed for, you need to:

  • identify what you are using
  • search online for the combination of things you are doing and how to to achieve what you want.

There may be more than one solution to try.

Additional reading in the official docs:

Finally, here are some notes on UI Anchoring, Scaling, CanvasScaler, etc: