MeldID: Unified Portable Profile for Secure Access and Data Management

Today, a single person can use dozens of online services. Almost every one of them requires creating an account and repeatedly filling profiles: name, phone, address, payment details, and other data.

Although modern Single Sign-On mechanisms greatly simplify authentication, re-entering profile data in many services remains a common issue.

Essentially, MeldID addresses two often-separated tasks: user authentication and controlled transfer of profile data.

Not Just Login

MeldID is an open digital identification management service available to anyone. It is accessible via meldid.de and designed not only for MELD® products but also for external applications.

The first scenario is familiar to almost everyone: the user chooses to log in through MeldID in a connected service. After successful authentication, a local session is established.

But besides login, you can pre-fill information that might be needed not only for authentication:

• Name, surname, and display name;

• Phone number;

• Preferred language;

• Country and address;

• Recipient's name;

• Company name;

• VAT ID, e.g., German USt-IdNr.;

• Separate tax number;

• Date of birth.

All fields are optional. You can provide only minimal data or prepare expanded information for orders, contracts, and business transactions.

The key idea is not centralized data storage per se, but the ability to reuse data where it is truly necessary.

How It Works in Practice

The user registers with MeldID and fills out the necessary sections. Then they choose to log in via MeldID in a connected service.

The application requests the needed information—it may be just name and email or an extended set including phone, address, and payment details.

After the user agrees, access to the selected data fields is granted, and the application receives only the requested information. If data were entered manually earlier, the service might prompt the user to confirm or update it.

On subsequent interactions, if data has changed, the connected application can request updated information. This eliminates the need to repeatedly edit identical profiles across different systems.

For example, a user visits an online store, an insurance company, and a booking service—each requires some repetitive information. Once prepared, this data can be reused safely, with permissions managed for each service.

This Is Not Auto-Fill for Any Website

MeldID is not a browser extension that automatically fills out forms.

Integration requires connecting to the service via API using OAuth 2.0 and OpenID Connect. Only after this can the application request user data and use it within its interface.

Therefore, MeldID should be regarded as a portable profile for connected applications rather than as a universal automatic browser filler.

How It Differs from Google and Apple Solutions

Google and Apple have similar features but designed for different purposes.

According to Apple’s documentation, Sign in with Apple is meant for registration and login via an Apple account. It provides only the data the user has permitted—tokens, authentication results, and selected details. (Apple Documentation)

Google Chrome supports saving and autofilling addresses, passwords, and payment data within Google Account and Google Wallet. (Google Documentation)

MeldID combines elements of both approaches, integrating them into a unified model. This is not just login or autofill within a platform but a mechanism allowing connected applications to access controlled and consented user information.

Data Control

Access to information is not granted automatically in full. Each request requires permissions such as:

• Basic profile;

• Contact details;

• Address;

• Payment data;

• Expanded information.

The user can see what data is being requested and decide what to share—separately for each service.

Password is never transmitted to the application. It only receives the result of successful authentication and the permitted profile data.

Benefits for Businesses and Developers

Integrating with MeldID reduces repetitive forms and accelerates registration processes. Customers complete authorization faster and more reliably, with fewer errors, while developers get a ready-made infrastructure for storing profiles and data transfer mechanisms.

MeldID can be useful for:

• Online stores;

• Subscription services;

• Booking platforms;

• Insurance and financial companies;

• Provider dashboards;

• B2B platforms;

• Event applications;

• Invoicing and document management services.

For instance, a buyer can pass their address and recipient’s name to the store, a client of an insurance company can share contact details, and a company representative can provide tax and registration data.

The integration module does not require abandoning local registration—MeldID can act as an additional, not replacement, login mechanism.

Open Yet Controlled Access

MeldID is an open platform accessible to everyone. External applications can apply for integration.

However, this does not mean they get unrestricted access. For each client, restrictions are set—allowed addresses, scopes, integration parameters. Protocols like OAuth 2.0, OpenID Connect, Authorization Code Flow, PKCE, and consent screens are used.

All processes are transparent for the user: they see who is requesting which data. For developers, a single integration mechanism applies across different services.

MeldID does not replace existing local accounts and does not mandate uniform operation of systems. It adds a layer of a portable profile, managed by the user and shared only with trusted applications.

In an era of numerous online services, not only is single sign-on important, but also transferring data without repeatedly filling out forms. The core idea of MeldID’s architecture is to enable users to prepare a profile once and decide independently where and how to use it.