zcalcu vs Krypta ECC

zcalcu is a 2 in 1 chat and calculator app. This app can be swapped between a chat application and a simple calculator. Its main features: -Setting the app type in calculator mode by calculate default secret key "17-08-1945". -Setting the secret key. -Change app type and icon between calculator and chat. -Chat a friend by a username with picture, and text. -Automatically disappearing recent message in 2 days

Krypta ECC is a privacy-focused communication app that looks and functions like a regular calculator, but behind a secret code lies a secure, end-to-end encrypted chat system. It's designed for users who want private conversations without drawing attention. A Calculator with a Secret At first glance, Krypta ECC appears to be a simple, fully functional calculator. You can perform normal operations like addition, subtraction, multiplication, division, and percentage calculations. It works exactly as any standard calculator would. However, when you enter your personal secret code and confirm it, the app unlocks a hidden chat interface. Only you know how to access it, making your private messages truly discreet. Private and Secure Messaging Behind the calculator is a fully featured chat system, designed for direct and private communication between users. Each user creates a unique username and a personal app code. The code is stored locally and never shared with any server, ensuring that your access to the chat is entirely secure and private. You can start conversations in two ways: • By username: search and connect directly with another Krypta ECC user. • By invite link: share or open a secure link that instantly starts a chat connection. The messaging interface is simple and familiar, featuring real-time text communication, timestamps, delivery and read indicators, and privacy settings. You can also block unwanted contacts or report misuse directly in the app. End-to-End Encryption Every message you send or receive is protected with end-to-end encryption (RSA-2048 + AES-256-GCM), meaning only you and your chat partner can read the conversation. Even Krypta ECC's servers cannot decrypt or view your messages. All encryption keys are generated and stored locally on your device, never uploaded or shared. Messages are automatically deleted after delivery, ensuring your conversations remain private and temporary. Powered by Firebase Technology Krypta ECC uses Google Firebase to provide reliability, speed, and scalability: • Firestore: Real-time chat and message storage • Firebase Authentication: Secure and simple user management • Cloud Functions: Serverless automation for invites and moderation Discreet and Intuitive Design The app is designed for maximum discretion. No one will ever suspect there's a hidden chat behind your calculator. You can quickly return to the calculator screen at any time with a simple gesture or tap, making it safe to use in public or shared environments. The interface is clean, minimalist, and familiar. Whether you are calculating something or chatting securely, the experience is smooth, fast, and distraction-free. Privacy by Design Krypta ECC is built around privacy principles. Your personal information, conversations, and contacts are not tracked, analyzed, or sold. Only the essential data required for functionality is stored. The app follows GDPR-compliant data handling and allows you to delete your account and all related data at any time. No advertising, no tracking, no profiling — just secure, private communication. Content Moderation Krypta ECC includes comprehensive content moderation: • Automatic filtering of objectionable content • Report functionality for inappropriate behavior • Block functionality to remove unwanted contacts • Developer contact information available in Settings • All reports reviewed within 24 hours