Nokia allowed people to receive 72x14, 1bpp pictures over a series of binary- or hex-encoded SMS messages, and have them show up instead of their carrier name on the home screen. In the 2000s, magazine ads and webpages would distribute them using premium-SMS.
This service, also featuring ringtones, games etc. has been revived, free of charge, by MtF hacker @[email protected] of the Chaos Computer Club. You can go to Blåmba.de and download all kinds of content into your retro phone.
The service has been discussed in detail at her 38C3 talk: media.ccc.de / YouTube mirror
I also made 10 logos mostly related to Blåhaj, these are already in the Blåmba logo repository.
I welcome feedback and suggestions for future logos!
I love these and immediately went to dig out an old Nokia to try them but I can't really seem to figure out how. Sending an SMS to register immediately responds with "die Kurzwahl ist nicht vergeben" (number not assigned).
It's not very clear on the website or in the talk but Blåmba normally only runs on CCC event networks. However, if you privately chat with Manawyrm she can fire up her modem on a commercial network and send you the SMS manually. Make sure to know which operator (by MCC/MNC) the logo should be assigned to, you can't store ones for other networks.
Without bothering Manawyrm, you can also try Ringtonetools (source-available program which Blåmba uses) to convert the pic into SCKL (hex-encoded) messages that can be sent from any phone, as opposed to the binary ones that are 2x more efficient but you need to directly interface with a GSM modem for.