Upvote:6
According to this website from an independent travel guide:
The mobile phone signal on the island only works in Hanga Roa and not always correctly. Cuts in calls or coverage failures are common. Timidly it is extended to other places of the island like Rano Raraku, and it is hoped that soon it will be able to arrive at Anakena beach.
In the (presumably) original Spanish:
La señal de telefonía móvil en la isla sólo funciona en Hanga Roa y no siempre correctamente. Son habituales los cortes en las llamadas o fallos de cobertura. Tímidamente se va extendiendo a otros lugares de la isla como Rano Raraku, y se espera que en breve pueda llegar a la playa de Anakena.)
Note that the above-linked pages are undated. The website's blog does appear to have been updated recently, but it is not clear how recently this description of the cell phone coverage was written.