Media
Media files in Grindr are stored on cdns.grindr.com:443 hosted by Amazon CloudFront powered by AmazonS3. All CDN files are accessible without authorization but some are protected with signed URLs. No security headers or Authorization need to be present in reuqest to CDN.
Caching is supported via ETag header — MD5 hash of image file. Image files might have image/jpeg, image/png or image/webp type, based on original.
Media files are identified by either a 40-character (public files) or 64-character (signed files) hexademical string. Although not confirmed for all types of media, it appears to be SHA-1 hash for 40-character hash and SHA-256 hash for 64-character hash. Confirmed cases: Audio uses SHA-256 for its 64-character mediaHash.
There are two types of files stored on CDN.