Last updated: May 2026
We take the protection of your personal data very seriously. Personal data is processed only in accordance with applicable data protection laws, in particular the General Data Protection Regulation (GDPR).
Personal data is any information relating to an identified or identifiable natural person.
CarbVista is an app for estimating nutrition information from meal photos. The app lets users take or select a meal photo, optionally add additional information, send the request to a backend server for analysis, and view estimated calories, carbohydrates, protein, fat, detected foods, confidence information, details, and warnings.
This privacy policy explains which data is processed when using CarbVista.
Christian Rothhaar
Querweg 4
25336 Elmshorn
Germany
Email: christian.rothhaar@gmx.net
CarbVista processes personal data only to the extent necessary to provide the app, secure the service, prevent abuse, manage free usage limits, provide optional account functionality, and enable subscriptions.
The processing includes:
CarbVista does not display advertising and does not use Google AdMob.
To analyze a meal, the app sends the selected or captured image to the CarbVista backend server. The backend processes the request and forwards the image, together with optional additional information entered by the user, to an AI service provider for analysis.
The following data may be processed for meal analysis:
Meal photos are transmitted to the backend only when the user actively starts an analysis. The backend does not permanently store the original meal photo. The backend may temporarily process the image in memory or in temporary processing steps required to perform the analysis.
For service operation and troubleshooting, the backend stores analysis audit metadata such as request time, success or failure status, technical image metadata, used AI model, device identifier, IP address, and user reference where applicable. Optional additional information entered by the user and complete analysis responses are stored server-side only if the corresponding backend audit configuration is explicitly enabled. The image file itself is not stored in this audit data.
The analysis result is an estimate and is not medical advice.
Our legitimate interest lies in operating the meal analysis service, preventing abuse, troubleshooting technical problems, and maintaining service reliability.
CarbVista uses OpenAI services to analyze meal images and generate nutrition estimates.
For this purpose, the backend may transmit the meal photo and optional additional information entered by the user to OpenAI. The response from OpenAI is processed by the backend and returned to the app.
Data transmitted to OpenAI may include:
Users should avoid including sensitive personal information in photos or additional text unless it is necessary for the intended analysis.
More information about OpenAI’s privacy practices: https://openai.com/policies/privacy-policy
CarbVista offers optional Google Sign-In for account creation and login. Google Sign-In is used to identify the user securely and to link usage, quota, and subscription status to an account.
When using Google Sign-In, Google may provide the following data to CarbVista:
CarbVista does not receive or store the user’s Google password.
The backend validates the Google ID token and then issues CarbVista’s own app session tokens. Session tokens are used to authenticate requests to the backend. Refresh tokens are stored by the backend only in hashed form.
More information about Google Sign-In: https://support.google.com/accounts/answer/12921417
CarbVista may offer paid subscriptions through Google Play Billing. Subscriptions are used to provide extended usage limits or premium access.
Payment processing is handled by Google Play. CarbVista does not receive or store full payment details such as credit card numbers or bank account details.
For subscription handling, the following data may be processed:
This data is used to verify and manage subscription status, provide premium access, prevent abuse, and handle support requests.
Subscriptions can be managed through Google Play: https://play.google.com/store/account/subscriptions
The app communicates with a backend server to provide its functionality.
During this process, the following data may be processed:
IP address
Used for security, stability, debugging, rate limiting, and abuse prevention
Pseudonymous device identifier (generated device ID)
Used to recognize requests, manage free usage limits, and prevent abuse
Authentication data
Used to maintain logged-in sessions and protect authenticated requests
Usage and quota data
Used to determine remaining free analyses and subscription-based usage limits
Request and response metadata
Used for debugging, support, and service reliability
The generated device identifier does not directly identify a person by itself, but it may be linked to usage data and, if the user logs in, to the user’s account.
CarbVista may use Google Play Integrity for security and abuse prevention. Where this protection is enabled, the app requests an integrity token from Google Play for protected analysis requests and sends that token to the CarbVista backend. The backend uses the token to verify that the request comes from the expected app and to evaluate integrity signals required for abuse prevention.
The integrity token is used for verification of the protected request and is not used by CarbVista for advertising or profiling.
Server-side data is stored only as long as necessary for the purposes described in this policy or as required by law.
In particular:
CarbVista may store data locally on the user’s device to provide app functionality.
Locally stored data may include:
Saved meal analyses and local meal diary entries are separate local app functions. Saved meal analyses keep the selected locally saved image and the analysis information for later viewing. Diary entries keep fixed nutrition values and a small local thumbnail for tracking purposes.
Local data remains on the user’s device unless it is sent to the backend as part of an analysis, authentication, billing, or other user-initiated request described in this policy. Users can delete supported local data inside the app, or remove local app data through the Android system settings.
CarbVista may request Android permissions required for its functionality.
These may include:
Camera access
Used to take meal photos for analysis
Image/media access or share intent handling
Used when the user selects or shares an image with the app
Internet access
Used to communicate with the backend server, Google Sign-In, Google Play Billing, Google Play Integrity, feedback handling, and analysis services
Permissions are used only for the app functionality described in this policy.
CarbVista offers a voluntary feedback form in the app. Feedback is intended to help improve the app and its analysis experience.
The feedback form may process:
Feedback is stored without account, device, meal image, or meal analysis reference. Users should not include personal data or sensitive information in feedback text.
As with other requests to the backend, technical server communication and security logging may process request metadata such as IP address, request time, and technical access information for security, debugging, and rate limiting purposes.
Our legitimate interest lies in understanding voluntary user feedback and improving CarbVista.
Personal data may be shared with the following categories of recipients:
Data is shared only to the extent necessary for the respective purpose.
Some service providers may process data outside the European Economic Area, including in the United States.
Where data is transferred to countries outside the European Economic Area, appropriate safeguards are used where required, such as Standard Contractual Clauses approved by the European Commission or other legally recognized transfer mechanisms.
There is a possibility that authorities in third countries may access personal data under local laws.
We store personal data only as long as necessary for the purposes described in this policy or as required by law.
In particular:
Users may request deletion of their account and associated personal data through the online deletion request form: https://ml.rothhaar.ipv64.de/request-delete
Users may also contact: christian.rothhaar@gmx.net
The deletion request form processes the information needed to handle the request. This may include the submitted email address, optional user ID, optional message, request time, IP address, and browser user agent.
When an account is deleted, personal data associated with the account will be deleted unless retention is required for legal obligations, billing records, security, fraud prevention, or the establishment, exercise, or defense of legal claims.
Local data stored on the user’s device can also be removed by deleting saved analyses and diary entries in the app where supported or by deleting the app data through Android system settings.
Under the GDPR, you have the following rights:
To exercise your rights, please contact: christian.rothhaar@gmx.net
You have the right to lodge a complaint with a supervisory authority, in particular in your country of residence or with the competent supervisory authority in Germany.
Data transmission between the app and the backend is encrypted using HTTPS (TLS), where the production backend is used.
CarbVista uses technical and organizational measures intended to protect personal data against unauthorized access, loss, misuse, or alteration. Session tokens and billing purchase tokens are handled with security measures such as hashed server-side storage where applicable.
CarbVista does not display third-party advertising and does not use advertising SDKs such as Google AdMob.
If advertising is introduced in the future, this privacy policy will be updated before such functionality is used.
CarbVista uses automated analysis to estimate nutrition information from meal photos. The result is an informational estimate generated by AI and should not be treated as medical, dietary, or professional advice.
CarbVista does not use automated decision-making that produces legal effects concerning the user or similarly significantly affects the user within the meaning of Art. 22 GDPR.
We reserve the right to update this privacy policy to reflect legal, technical, or functional changes.
The current version will be made available in the app or through the app’s store listing.
Information according to Section 5 TMG / Section 5 DDG
Christian Rothhaar
Querweg 4
25336 Elmshorn
Germany
Contact:
Email: christian.rothhaar@gmx.net
Electronic contact via email is sufficient and responses will be provided promptly.