The book was definitely an eBook, possibly on Amazon. I'm fairly sure it was written in the last couple of years as well!
The sequel was in progress when I read the first novel a few months ago and the author posted up the first chapter of the second book where the main character had his powers taken away from him and was sent to hell by the magicians. I distinctly remember a few things but after a few hours of various searching methods I came up clear. Here's a few of the things I remember.
The main character had lost his mother, his father was distant, and a humanoid kind of frog alien was granting superpowers to people in the hopes of creating someone who could defend them from superior aliens they were warring with. These super powered people could defeat enemies and absorb some power, effectively levelling up. The unwilling protagonist at first declined the powers and wasn't interested until he realized his brother was being targeted by the evil aliens. The 'evil' aliens periodically sent out drones/scouts which the unwilling protagonist defeated to grow in power, building to a massive fight in a bigger city. Also there were wizards/witches with magical powers. Demons were somehow involved at the end as well.