What free cross-platform benchmark tools do you use to benchmark phones?

I bought a handful of Costco $130 Android LG Stylo 3 Plus phablets as
stocking stuffers that I wish to benchmark against my sister's $670 iPhone
7 Plus.

T-Mobile LG Stylo 3 Plus (aka TP450):
https://www.t-mobile.com/cell-phone/lg-stylo-3-plus
http://www.lg.com/us/cell-phones/lg-TP450-stylo-3-plus
https://www.gsmarena.com/lg_stylo_3_plus-8694.php
T-Mobile Apple iPhone 7 Plus:
https://www.t-mobile.com/cell-phone/apple-iphone-7-plus
https://www.apple.com/iphone-7/specs/
https://www.gsmarena.com/apple_iphone_7_plus-8065.php

I can compare them based on pure hardware specs but benchmarks are better:
https://www.phonearena.com/phones/compare/LG-Stylo-3-Plus,Apple-iPhone-7-Plus/phones/10534,9816

The problem is most Internet benchmark test results are platform specific:
https://www.androidbenchmark.net

And most free benchmarking tools seem to only work on one platform:
https://www.greenbot.com/article/2843337/test-your-android-phones-performance-with-these-free-benchmarking-tools.html

Hence the consumer-available cross-platform benchmark question:
Q: What free cross-platform benchmark tools do you use to benchmark phones?