CallShield protects elderly people from phone fraud — locally, privately and in real time. No cloud, no data transfers.
The new threat
Scammers can clone a family member's voice in seconds. A short clip from social media is enough.
Large language models create tailor-made conversation flows — more convincing than ever before.
What used to be individual calls are now thousands of simultaneous, personalised attacks.
Features
Built for Swiss households. Local, understandable and easy to use.
Detects scam patterns like grandparent scams, fake police and tech support fraud during the call.
No cloud, no data transfers. All analysis runs directly on the device — your calls stay private.
Green, yellow, red — instantly visible. Large display and calm prompts that don't confuse.
Suspicious calls automatically notify family members — without sharing the conversation.
Threats
The most common phone scams in Switzerland — all covered with specific detection patterns.
"Your grandson had an accident and needs money immediately."
"This is the cantonal police. Your bank account is compromised."
"We detected a virus on your computer."
"Send CHF via TWINT to verify your account."
Cold calls about crypto and trading investments.
"Install AnyDesk/TeamViewer for support."
How it works
CallShield connects between your router and your phone — done.
CallShield connects to your router. Compatible with Swisscom, Sunrise and Salt.
For every call, CallShield analyses the caller ID and checks it against known patterns.
During the conversation, the device detects suspicious phrases and pressure tactics.
The traffic light shows the risk level. In case of danger, you get clear guidance and family members are notified.
Technology
No cloud. No recordings. No compromises.
Roadmap
CallShield is developed step by step — from simple rules to intelligent detection.
Market research, legal review, user interviews
SIP proxy on Raspberry Pi 5, caller ID, notifications
Keyword detection, Swiss scam patterns, traffic light UI
Speech-to-text, learning detection, dialect analysis
FAQ
CallShield is in development. Sign up to receive updates and be the first to know.