Best Windows desktop apps for emulated Mobiles & Tablets (Like blisk!)

I'm new to the web development world, just got a job as a junior dev. I've built something with HTML, CSS & JS. But some functions didn't work quite well on my phone. so I need to start doing mobile app development. My co-worker has told me about this app called Blisk, It's a great one, but I was just wondering what you guys use for mobile & tablet development. Would like to try out few apps before!

Thanks!!