Method for checking the identity of a person on the basis of an identification document by means of a mobile communication device, the identification document having an electronic circuit, the mobile communication device having an image camera, and the method comprising the following steps: Capturing a biometric feature of the person by means of the image camera of the mobile communication device in order to obtain a captured biometric feature; Reading out a biometric reference feature from the electronic circuit of the identification document by means of the mobile communication device; and Comparing the captured biometric feature with the biometric reference feature by the mobile communication device in order to check the identity of the person wherein for reading the biometric reference feature from the electronic circuit of the identification document an electronic certificate of the mobile communication device is exchanged between the mobile communication device and the electronic circuit of the identification document in order to authorize the mobile communication device vis-à-vis the identification document, wherein the electronic certificate is retrieved by the mobile communication device from a certificate server via a communication network, wherein the electronic certificate is stored in a memory of the mobile communication device, and wherein the electronic certificate is read out from the memory by the mobile communication device and is transmitted to the electronic circuit of the identification document, wherein data from a machine-readable zone of the identification document are also captured by means of the image camera of the mobile communication device in order to check the authenticity of the identification document, wherein the acquired data are transmitted to a test server via a communication network by means of the mobile communication device, and wherein the authenticity of the identification document is checked by the test server, wherein the test server is a server, on which data for checking the authenticity of the identification document are pre-stored, wherein the test server checks the authenticity of the identification document by a comparison of the transmitted data with the pre-stored data, wherein in case of a match of the transmitted data with the pre-stored data the authenticity of the identification document is existent, wherein further the mobile communication device performs further requests, the requests being related to the person, by using the data which have been captured from the machine-readable zone of the identification document, in order to provide further data which are useable for checking the identity of the person, wherein the further requests, the requests being related to the person, are directed to the test server. Capturing a biometric feature of the person by means of the image camera of the mobile communication device in order to obtain a captured biometric feature; Reading out a biometric reference feature from the electronic circuit of the identification document by means of the mobile communication device; and Comparing the captured biometric feature with the biometric reference feature by the mobile communication device in order to check the identity of the person wherein for reading the biometric reference feature from the electronic circuit of the identification document an electronic certificate of the mobile communication device is exchanged between the mobile communication device and the electronic circuit of the identification document in order to authorize the mobile communication device vis-à-vis the identification document, wherein the electronic certificate is retrieved by the mobile communication device from a certificate server via a communication network, wherein the electronic certificate is stored in a memory of the mobile communication device, and wherein the electronic certificate is read out from the memory by the mobile communication device and is transmitted to the electronic circuit of the identification document, wherein data from a machine-readable zone of the identification document are also captured by means of the image camera of the mobile communication device in order to check the authenticity of the identification document, wherein the acquired data are transmitted to a test server via a communication network by means of the mobile communication device, and wherein the authenticity of the identification document is checked by the test server, wherein the test server is a server, on which data for checking the authenticity of the identification document are pre-stored, wherein the test server checks the authenticity of the identification document by a comparison of the transmitted data with the pre-stored data, wherein in case of a match of the transmitted data with the pre-stored data the authenticity of the identification document is existent, wherein further the mobile communication device performs further requests, the requests being related to the person, by using the data which have been captured from the machine-readable zone of the identification document, in order to provide further data which are useable for checking the identity of the person, wherein the further requests, the requests being related to the person, are directed to the test server.