For pytorch-android 1.5.0 size of the aar is 25mb,
https://bintray.com/pytorch/maven/org.pytorch%3Apytorch_android/1.5.0#files/org%2Fpytorch%2Fpytorch_android%2F1.5.0 23
Nightly builds are a bit bigger.
What is the size of your vision model that you pack in application?
(As an idea to have smaller model you may try to use quantized model or models with smaller size like mobileNetV2 or download model on the device at runtime)