Quotation from
https://en.wikipedia.org/wiki/Digital_Telecommunications_Philippines#PLDT_buys_Digitel
After the acquisition and assessment of the Digitel network, The company was announced to delisted from the publicity in the Philippine Stock Exchange (as its stock quoted: DGTL) effectively between from late 2011-2012, and its subscribers were transferred into the PLDT network with its services were shut down. This became effective from November 15 - December 31, 2012, when the last Digitel Business Centers were closed.[2] However, Digitel retains operation on the services of its subsidiary Sun Cellular.
as of 04 Feb.2017.
My own personal experience: As of Nov.2016, SMART communications, the first 'daughter' of PLDT for mobile connecting, was ordered by PLDT to improve all SUN signal posts[no quotation available or possible=nqap], thus SMART gave their 3G and antennas [nqap] to the SUN system so from then onward, all SUN mobile devices display "roaming". This step has strongly improved the SUN signal and coverage all over, ending a nearly 1-year season of extremely poor and slow coverage. In exchange, now as of Dec.2016, the formerly reliable SMART 3G net is down and as slow as SUN had been before [nqap] - they swapped their antennas and frequencies. It means that former SUN users who turned away from SUN for stronger and better 3G connections are now at SMART in the very same mess.[own sad experience] SMART has announced in Dec.2016 to improve their whole antenna system into 4G and has already proudly announced the completing of it for the capital Manila during Dec.2016.[telegoegraphy.com] In Cebu City, the Philippine's second biggest metro-city, the work is underway and the 3G services are next to zero; the only feature working well is the uploading of money load to the system, i.e. you can easily book for any tariff by paying online but you will never have a satisfying signal ! All the wiki-pages concerning SUN or SMART are thus outdated ! ! !
No quotations are possible from the homepages as Philippine companies in general NEVER mention any unfortunate points of their business. No infos are available and most recently, they even changed their IP names like SUN became mySun or SMART became mySmart, thus securing their old pages to no more show up. Any info can only be retrieved from independent sources, like newspapers, telecom info platforms like www.telegeography.com and other sources.
as of 04.Feb.2017