The OneBlade is the single easiest recommendation on this site. It occupies a genuinely useful gap: a razor shaves bald and a trimmer will not go below 1 mm, and the OneBlade does both ends plus everything between, with a blade that never touches skin. If you keep stubble, keep a short beard, or shave your neck and cheeks around a beard line, this replaces two devices and does the job better than either.
The sensitive-skin case deserves the emphasis it gets. The dual-sided blade oscillates behind a guard, so it cuts hair at the surface without dragging, twisting or pulling the way a rotary head does and without the close skin contact of a wet razor. For men who get razor bumps, ingrown hairs or post-shave rash — a very common complaint on coarse, curly Indian beard hair — this is the machine that solves the problem rather than managing it.
Be clear-eyed about the running cost, because it is the one thing buyers get wrong. The blade is a consumable, not a permanent part, and at roughly ₹899 every four months you will spend more on blades in year one than you spent on the device. That is still good value for what it does, but it makes the OneBlade a poor choice for someone who trims once a month — a BT3211 with self-sharpening blades is cheaper to own. Buy the OneBlade because you groom often, not because it is cheap.