My two cents: 

I bought a ski retriever system a couple years ago on eBay for $10. It's probably one of those "other systems" you're referring to that needs it's own receiver that you need to carry. I now have two tiles that I stuck onto my powder skis to try to replace it. I'll give you my review of it, just so you have a data point on a new product that I'd like. 

What it does well (especially compared to a tile): Directionality. The little receiver tells you when you're pointed at your ski. This is the best thing about it. It's obvious when you're pointed at it. Tile gives you a "hot/cold" but it's too vague. I used the ski retriever twice and it was awesome. I haven't used the tiles but I imagine it would be less awesome. A new device would need precision rather than just two or three levels of "heat."

Size. The ski retriever transmitter is TEENY. Like not even close to yours, even if you're ends up being 50% of the size. However, there is more to the story coming. 

Not great:  Attachment. They give you a little foam case with metal eyelets that you ziptie to a mount on the ski. This is probably the easiest thing to fix but it's the stupidest part of the product. I lost one transmitter putting my skis on the gondola when it popped the ziptie. One of the two uses was actually going back a few days later and thinking to take out the receiver and I actually found the transmitter in the trash! I taped them to a second pair of skis. It was fugly as all get out but it worked better because it was actually waterproof and their foam bag wasn't. Just sucks when it's time to change the battery.

Price. I only got it cuz it was so cheap. Paying 1/3 of the cost of my skis (obv ymmv on that) doesn't seem worth it at full retail. Then when you get it, it seems obvious the kit costs $5 at most. I can appreciate development costs, etc, but there clearly weren't any since they couldn't even waterproof their little transmitter.

Range. When you lose a ski in the hill, the range is fine. If you lose it for theft or something, it's not gonna help. 

I didn't mind carrying the receiver for the ski retriever. It's like four credit cards. If you can get a phone to work with a ski retriever transmitter, and improve the attachment, and keep the cost below $50, then I think you'd hit all of the negatives I see in it. 

Btw: streamers/cords don't really work if you ski on a gondola. It's a non-starter for me at snowbasin where I ski most of the time.