The filename "threema-the-secure-messenger-v4-v2795-univ-64bit-os150-ok15-user-hidden-bfi2-ipa" represents a specific iOS App Store Package (IPA) for the Threema messaging app, likely from a third-party source featuring modified ("user-hidden") tags. Threema is a Swiss-based, zero-knowledge, and metadata-restrained messenger that ensures all communications are encrypted with NaCl on the device. For more information, visit Threema . Threema. The Secure Messenger - App Store