Their interview questions are pretty basic and the whole product is pretty much useless. Waste of time and money.
ABCs of Product Management - Children's book about Product Management
LeetCode - Practice and level up your development skills and prepare for technical interviews.
MODI - Create anything you want with robotics of things
HackerRank - HackerRank is a platform that allows companies to conduct interviews remotely to hire developers and for technical assessment purposes.
Quadbot - Build your own Robot
Daily Coding Problem - Get exceptionally good at coding interviews