PLDT’s mobile arm Smart Communications has launched a new promotion offering ‘unlimited’ on-net mobile calls through its ‘Smarttalk’ plan, BusinessMirror reports. Unnamed sources say Smart will charge PHP500 (USD10.3) per month for unlimited calls on the operator’s network. The promotion is open to Smart and Piltel’s ‘Talk ‘N Txt’ subscribers whether their subscription is on a post-paid or pre-paid account.