Amnesty International has told Stormont ministers it is concerned that a coronavirus tracking smartphone app "could open the door for a much greater degree of state surveillance and privacy rights infringement".
The app has been downloaded more than 55,000 times since being piloted on the Isle of Wight before being rolled out nationwide.
Amnesty said it has written to the Executive raising concerns about data privacy and human rights protections related to any Covid-19 tracking app adopted in Northern Ireland.
Concerns have already been raised about whether former and serving security workers in Northern Ireland would feel uneasy about using the app.
In the past, retired and serving RUC and PSNI officers have had to move house under threat after data leaks.
Amnesty said: "Contact tracing apps and other technology could potentially be useful tools in responding to Covid-19 and helping Northern Ireland to emerge from lockdown, but there are legitimate concerns about possible infringement of human rights."
In the letter to Health Minister Robin Swann and copied to all ministers, Patrick Corrigan of Amnesty wrote: "We urgently need clarity from the Executive if you plan to follow the British Government in adopting the NHSX tracking app which uses a centralised database, or the more privacy-preserving models of the Republic of Ireland and other European governments.
"While most European states are now opting for a decentralised, privacy-preserving model, the UK Government appears to be planning to route data through a central state database.
"We are concerned that this could open the door for a much greater degree of state surveillance and privacy rights infringement, with the potential for integration with other state databases."
Amnesty also registered its concern that contact tracing apps developed for use on either side of the Irish border may be incompatible, thus making it harder to control the spread of the virus.
Meanwhile, NHSX has admitted that Huawei and some older mobile phones cannot run the NHS contact tracing app being trialled.
Dr Geraint Lewis, who is in charge of the development of the NHS Covid-19 app, said that the new tool will only work with newer operating systems on Apple and Samsung phones.
Speaking to BBC Radio Solent, he said phones needed to have the capability of running Bluetooth Low Energy (BLE) and to be running either Apple ios 11 upwards or Android 8 upwards.