This led to a massive cultural shift. Users didn't just download apps; they had to "Sign" them. Forums were flooded with people posting their IMEI numbers, hoping someone with a "Developer Certificate" (DevCert) would sign a file for them. It was tedious, but it was the only way to get apps like X-plore or UltraMP3 to work.
To work with these ROMs, the community historically relied on a specific suite of tools: s60v3 rom