Solo dev from UG built this on his phone

什么是 Solo dev from UG built this on his phone？

What it solves: Linear equations (ax + b = 0) Quadratic equations (ax² + bx + c = 0) Cubic equations (ax³ + bx² + cx + d = 0) Radical expressions (√(expr) = expr) Rational equations (p(x)/q(x) = r) Literal equations (solve for any variable) What makes it different: Shows every step explained in plain English Verifies the solution by substituting back Custom equation keypad (no fiddling with keyboard) 100% offline — no internet needed Free AI trials included