Six preset amounts, one custom field.
The recharge form shows six preset amounts in AED — 20, 50, 75, 100, 150, 200 — and a custom input below. That combination looks obvious in hindsight. It was not.
Where the numbers come from
Two months of requests, grouped by the amount people asked for. Three peaks stood out: a small one at 20–30 AED (top-off requests), a bigger one at 50 AED (default bundle top-up), a third around 100–150 AED (monthly refill). We rounded the peaks to sensible chip labels and filled the gaps.
75 sits between 50 and 100 because a surprising slice of people ask for something like “70” or “80” — enough to warrant a chip halfway between. 200 is the ceiling for the chips because requests above it are rarer and usually come with a question we need to reply to anyway.
Why keep the custom input?
Because presets are always a lie for someone. If your remaining balance is exactly 63 AED and you want to round it to 100, you do not want to overshoot with the 50 chip and then have change. The custom field takes any integer between 5 and 500 AED.
It does bring some junk — someone types “20000” and hits send, an obviously off amount. The form catches those with the 5–500 range. Above 500, we route the request by email so a manager can eyeball it first.
One rule we broke
Design lore says: no more than five chips, or the eye stops parsing. We tried five (20 / 50 / 100 / 150 / 200). It saved half a line on mobile and lost us the “75 crowd”, which was noticeable in the numbers. The sixth chip earned its keep.