5 min
Reading crumpled paper
A drawer in the Lisbon office holds 4,182 receipts, one jar of them left in a car through a summer. 214 of them can no longer be read by anybody, which is a fact the reader has to live with.
Rui Cavaleiro
·
Machine learning engineer
6 min
Three days of watching people file receipts
Fourteen kitchen tables, one biscuit tin kept since 2011, and a shutter button in the wrong half of the screen. Most of what changed after the June visits had nothing to do with reading paper.
Nadia Okonkwo
·
User researcher
5 min
Running the reader on the phone
380 ms on an iPhone 14, 3.4 s on a Galaxy A13, and an import that Android kept killing at receipt 60. What it took to keep the reading on the device, and what it costs.
Marek Dudek
·
Mobile engineer
5 min
How we priced Slip
In March the price went from EUR 19 a year to EUR 29 and 1.9% of subscribers left. The reasoning behind both numbers, and the offer we turned down in 2025.
Elif Karabulut
·
Co-founder
4 min
No red numbers
A total set in red, an arrow pointing up, and a comparison against a month with a week away in it. Taking the judgement out of the interface was more work than putting it there had been.
Yuki Tanabe
·
Design lead
5 min
Sorting a supermarket receipt into one box
The first release had 41 categories and an “Other” bucket that swallowed 22% of everything within two months. What we changed, and the part no two households will agree on.
Priya Raghunathan
·
Product engineer