Don't Get Taken!
I recently got an email offering me 75% off a set of add-on lenses for smart phones, tablets, etc. The copy said they performed better than a DSLR and beat out lenses from some very well-known lens makers.
The company also said that I could get them at 75% off their normal price of $224 and that they are sold out in stores and now only available online at the special price of $56.00
Sadly for them I do some direct from China shopping on Wish.com and regularly see the same set for (wait for it) as little as ONE DOLLAR!
Add-on lenses are seldom very good, especially when not made for a particular camera or lens. There are just too many variations of design for a generic add-on to work with properly all the time.
Also the claims that these lenses somehow enable the camera to work better in low light is pure fantasy.