The Graham Dwyer murder trial is hearing evidence about 2 secret phones he's alleged to have used to contact Elaine O'Hara.
The 42 year old architect from Kerrymount Close, Foxrock, denies stabbing the childcare worker at Killakee mountain in August 2012.
Her skeletal remains were found in September 2013.
Crime analyst Sarah Skedd has resumed her evidence today.
She used cell site analysis to compare the locations of 3 mobile phones allegedly used by Graham Dwyer.
They are his work phone, a prepaid 083 phone and a so called 'master' phone found in Vartry reservoir along with a 'slave' phone.
The jury's heard that the 083 number was always active in the same locations as Graham Dwyer's work phone even when the architect was on annual leave in Co Cork on the 3rd April 2012.
There was evidence the two secret phones also appear to connect to cell sites in the south inner city of Dublin at times when the architect would have been at work on Baggot street.
Earlier today members of the public were warned by Judge Tony Hunt not to live tweet from the trial while it's sitting in the absence of the jury.
He said the reporting restrictions are in place for good reason.
