At Orange, Lovell was head of support operations for seven years, where he was responsible for multimedia technical operations and services.
He left Orange in February this year to join BT as service operations centre manager, which involved overseeing technical support teams responsible for NHS services provided by BT.
Lovell said: I am really looking forward to working with a team of people that already have an excellent reputation in the mobile arena.
One of my main objectives is to further develop Dialogues technical infrastructure and procedures, in order to continue to improve platform and service reliability.
Dialogue managing director Hugh Spear said: Steve will be an integral part of helping drive the business forward. His technical knowledge and expertise will help continue to improve Dialogues reliable platform.