Cell phone antennas - any luck? Any winners?

I had a Wilson mag mount antenna back in the day that I think helped my old Samsung flip phone.  That was maybe 2004. Phones had antenna connectors back then. 3G was the best stuff. Color screens were newfangled, and my phone didn't have a camera - it was an accessory that plugged in to the phone to send photos.  

That's a long time ago. I have a factory unlocked Samsung S8+ that I like, but I'm using it on a BYOD Sprint promo that has me paying $7 (taxes and fees only) for two smartphones and unlimited data, text and talk, and 10GiB tethering. 

I'm getting what I'm paying for.

It's slow, laggy, and generally worse than the AT&T service I gave up.

I'm thinking about getting an antenna setup again. Not looking at pricey powered amplifier setups. Not looking at GoTenna. Maybe setting a budget of $50, anyone have anything that worked? Could use something in my office and something on my car. 

Don't think your going to get any gains from an antenna. AFAIK there is no way to hook them to newer phones. 

That's being said, I have a WeBoost/Wilson powered 0ne that works well..... But not a $50 item. 

In reply to java230 :

Wilson used to sell an adapter that was a plate attached to a wire. The plate was supposed to affix to the outside of a phone that didn't have an antenna port. 

It looks like the current Wilson offerings work this way, but the plate is now integrated into a phone holder. 

I play a geolocation cell phone game called ingress, and improving cell connection in low data areas is a big thing, Wilson/weboost is definitely the ticket. Anything else is basically snake oil.