What Is Possible?

Digital Car Keys

Opening your own car without a key and even starting it without contact is already possible with a chip, app or smartphone. Various technologies such as Bluetooth or NFC technology are available for transmitting the necessary signals. The existing technologies are constantly being optimized – not least in terms of data security and data protection.


Opening a car without a key has advantages, especially in fleet management. Apps and virtual car keys can usually be conveniently integrated into existing systems via SDK and API. Even vehicles that are supposedly getting on in years can be retrofitted with modern technology and can thus be easily optimized. Ultimately, this opens up countless new possibilities for vehicle use – from shared use of a car to novel services such as in-car deliveries.

1. The Most Important Facts

  • A digital car key increases flexibility, especially for multiple authorized drivers at independent locations.
  • A typical area of application for keyless car access is fleet management.
  • Depending on the management system, it is quite easy to retrofit a car so that it can be opened with a smartphone.
  • Technologies such as Bluetooth and NFC guarantee high data security.
  • Most systems for using digital car keys can be easily integrated into existing systems via SDK and API.

2. Digital Car Access: Sharing the Car With the Smartphone

Systems for digital car keys have developed strongly. Both in the area of car sharing and in fleet management, the possibilities of a virtual car key show particularly clear positive effects. The greatest advantage results from digitization: Vehicles can be shared among several users without having to hand over a physical key. Instead, rights for vehicle use are conveniently set via app using a smartphone or tablet. The access rights enable contactless car access.


But the private car market is also catching up when it comes to digital keys: The first cars that can be opened without a key as standard are already available on the European market. However, if you would like to open your car without a key, for example with your smartphone, this is already possible. With flexible solutions such as key boxes that establish a connection between the smartphone and the box and can open it automatically, you can easily retrofit even older cars. Access authorizations are controlled via a corresponding app that allows access to the car.


For companies in particular, however, this technology opens up many possibilities. Managers of vehicle fleets can thus bypass the process of handing over the keys and automate the allocation of vehicles. Often, administrative tasks are still performed manually by fleet managers; as a result, valuable working time is lost. With the digital car key, this effort is eliminated: instead of handing over a physical car key to each driver and reclaiming it after the trip – possibly even at a different location – drivers receive virtual keys. This can only be used via authorized smartphones. Digital car keys thus shorten the process of vehicle handover in car rental, car sharing or corporate fleet.

Outlook: Digital Car Key for In-Car Deliveries

But opening a car via app can also bring completely new possibilities independent of car sharing. Have you ever heard of in-car delivery? According to this concept, deliveries can simply be left in a parked vehicle. The digital car key is transferred – with limited validity – to the supplier or service provider for this purpose. The latter is given one-time access to the trunk of the car, but cannot move it. In this way, goods, tools or other deliveries can be conveniently deposited in the vehicle, for example in an underground garage or in the company parking lot. The right car is usually located by GPS. Cleaning or repairs to the vehicle are also conceivable in this way.

3. How Digital Car Keys Work

Whether RFID, NFC technology or Bluetooth: a car can be opened digitally using various technologies. But which technology is best for you and what are the advantages of the different systems for the digital car key?


A pioneer in keyless car access was RFID technology. This was introduced in the 2000s. It was supposed to make it possible to simply open the car without a key. Instead, a chip acted as an opener, requesting access to the car via an encrypted signal from the car.

This digital car key technology, which is based on the transmission of radio waves, still exists today. The abbreviation RFID stands for “Radio Frequency Identification”. Depending on the variant, the door must be touched to open the car or, for example, a foot movement under the tailgate must be made to trigger the transmission signals. However, the system does not offer a completely virtual key. After all, a chip card is still needed to open the car without a key.

Advantages and disadvantages

One advantage is that the technology is already integrated as standard in many cars. There is no need for retrofitting. It is also possible to retrofit a car with central locking and open it without a key. However, this requires a sometimes complex and cost-intensive conversion. Another disadvantage of the technology is that a chip or chip card is required. This means that this technology does not work entirely without a physical key. The technology also does not always perform well in terms of security, since the RFID signal can be expanded almost without difficulty – which makes the car vulnerable to hacking attacks.

2. NFC-Technology

NFC technology is based on RFID, but requires the transmission signal and receiver to be in close proximity to each other. This is where the name of the technology, “Near Field Communication,” comes from. Although the two elements must be no more than a few centimeters apart, they do not have to be in direct contact. Many smartphones are equipped with NFC technology as standard. For NFC in the car, this means that if you approach the door handle with an authorized smartphone, it triggers the desired action and opens the car. In the future, the technology will even be expanded so that you can leave the smartphone in your pocket and only need to be near the car to open it.

Advantages and disadvantages

One advantage of NFC technology is the completely contactless car opening and the possibility of starting the car entirely without a mechanical key. NFC security is enhanced by the encrypted data exchange, which is carried out between the smartphone and the car receiver without the owner noticing. In addition, several authorized users can open the car door without a key. They only need to have access rights, which can be conveniently defined per user and smartphone. Likewise, NFC technology can be used when the cell phone battery has already given up. As a rule, the signal in the car ensures that sufficient energy is available to open the vehicle.

3. Bluetooth in a Car

Bluetooth also allows wireless data transmission. In contrast to NFC technology, however, the range is significantly greater. Depending on the signal strength, it can be ten to 100 meters. Bluetooth is currently used in cars to connect to smartphones, for example, to listen to music via the device or to make hands-free phone calls. The high security of Bluetooth also makes the technology suitable for transmitting signals that open the car without a key. An example of this use of Bluetooth in the car is a key box. This contains the physical car key. If an authorized person wants to open the car via an app, the smartphone sends an encrypted signal to the box via Bluetooth and triggers a mechanical lever. This activates the open button and unlocks the vehicle.

Advantages and disadvantages

The advantages of this system are the simple possibility of retrofitting through the flexible box, which does not involve any installation effort. This advantage scores particularly well in fleet management, as do the quickly set-up access restrictions via app. Another advantage of this digital car key is the availability of Bluetooth even independently of a cell phone signal. A disadvantage is the possible security gap that exists for a few seconds during a data transmission. If car thieves specifically exploit this, car hacking is possible. Modern encryption techniques such as a challenge-response method offer a high level of security here. In addition, Bluetooth devices can be hidden from third parties so that they are not displayed among the surrounding devices. This means that only authenticated smartphones can access the vehicle.

4. Digital Car Key Security

As the evaluation of the German Insurance Association (Gesamtverband der Deutschen Versicherungswirtschaft e.V.) from 2019 shows, car thefts are still a major issue in Germany. More than 14,000 cars with comprehensive insurance were stolen – naturally, this raises the question of how high car key security is without an actual key. For many consumers, the advantages of the virtual key appear to be disadvantages at the same time: Assigning access rights via smartphone or app could provide an easy entry point for hackers. However, highly secure authentication procedures for granting access rights speak against this. Moreover, assigned rights can be revoked quickly and easily: A stolen cell phone does not necessarily mean a stolen car.

However, the security of car keys from RFID technologies is the main subject of criticism. It is said to be relatively easy to extend the range of the radio signal between the car key and the car. This could theoretically allow thieves to gain access to the car and drive it until a restart is necessary. However, some manufacturers have already taken countermeasures and developed a special technology with computer chips that can close this security gap.

Data security is also increased by NFC technology. Here, the car usually interacts with the smartphone. Although NFC technology is based on RFID technology, it usually has a special “secure element” at the transmitter or receiver. A virtual car key is stored there, as is sensitive bank data for contactless payment, for example, and can thus be protected from third parties. Data protection is thus also ensured. The short transmission path of NFC between car and smartphone also leaves little room for car hacking. Car thieves would have to approach immediately to gain access. Another point in favor of NFC security is the encryption techniques: A dynamic code is generated for each car opening, which can only be used once and cannot be copied.

That leaves a look at Bluetooth technology in the car. Bluetooth security is stated as “high” due to the encryption. Although there is a short gap in which third parties could theoretically gain access – this only lasts for around one second. In addition, modern digital car key systems rely on multiple authentication processes that repeatedly check access rights. Furthermore, security can be increased by ensuring that the Bluetooth elements are not visible to outsiders at all times. It is generally recommended to switch on Bluetooth only for the duration of the planned transmission to ensure maximum data security.

5. Prerequisites for Digital Car Access

If a car is to be retrofitted for digital car access, the question of the requirements for a conversion quickly arises. But the technical requirements are not high. For example, to use RFID technology, your car only needs to have central locking. After the conversion, you can open your car with central locking without a key.


The requirements for a digital car key are also low for other systems. For a system with a key box that is opened via Bluetooth, only a key with electric buttons is required. After receiving the encrypted signal, the physical opening button of the car key is pressed in the locked key box to allow access to the car. Even older cars can sometimes be modernized in this way. Depending on the technical circumstances, the car can also be started using the smartphone. With some systems, for example, the cell phone can be placed in an NFC tray provided for this purpose and the car then started.

Digital interfaces for best possible integration

Do you have a fleet of vehicles and want to create a digital interface between the virtual car key and a modern fleet management system? Corresponding developer kits help you with the integration. These are software development kits (SDK) and application programming interfaces (API). An SDK, for example, provides instructions, documentation or test projects that show how to use the new product and how to integrate it into existing systems. An API, on the other hand, is a programming interface that helps to exchange information between the new and the old system. In this way, software related to the digital car key can be conveniently inserted into other systems.

Modular systems are particularly advantageous, as they allow new extensions at any time. One example: If you have already digitized your fleet of vehicles and equipped them with GPS receivers for fast tracking, a modular system allows you to equip the cars with a virtual key even after the fact. The digital interface ensures that you can easily add additional functions. It thus offers scope for developments and innovations in fleet management.

6. Digital Car Keys in the Fleet: The Advantages

Even from a small size, the smooth organization of a fleet is essential. The installation of a digital fleet management system can help. This enables an overview of the fleet’s vehicles at all times. Add-ons such as GPS transmitters in the individual vehicles increase convenience, as do digital car keys for all fleet vehicles.

The advantages of the virtual key are obvious:

The installation of keyless systems that work via Bluetooth or NFC technology, for example, is made possible and easy to implement for small and larger fleets alike by non-invasive methods. For example, you can start immediately after positioning key boxes in the car and assign access rights accordingly. You get peace of mind from the digital car key that none of the physical keys will be lost. In addition, the process of handing over keys to individual vehicles is shortened: There is no need for manual key handover among individual users, for example within a supply chain or in shift work with service vehicles.

Opening a car with a cell phone also secures competitive advantages and shows itself forward-looking. In particular, the combination of modern fleet management with keyless access to the fleet increases efficiency and promotes optimized utilization of existing cars and commercial vehicles.

7. Conclusion

The use of virtual car keys will become increasingly common in the future. Whether NFC technology or Bluetooth, security for the car key plays an essential role and is provided by encryption technologies. Non-invasive methods are particularly interesting for retrofitting keyless car access. These solutions can be installed quickly and easily, but increase convenience and application efficiency enormously and immediately.

Security, speed and convenience – these are also the three important keywords of our flinkey system. With the flinkey box, you can open your car via app without having to retrofit it at great expense. All you need is the key box, which is placed at any position in the vehicle. In the future, you will be able to open your car with your cell phone and upgrade all vehicles in your fleet with uncomplicated technology. Integration into existing fleet management systems is no problem. Please contact us if you would like to learn more about our concept for keyless access to your vehicle fleet!

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