Singtel has been the exclusive reseller for iPhone for the last 18 months or so. By end of this year, 2 more telcos will jump onto the bandwagon. The first is MobileOne (M1) Singapore.
M1 Singapore is the second telco to offer the Apple iPhone 3GS. They have put up a online site for preorders. If you are on M1 and wanted a iPhone, here is the link you can register your reservation.
No Price plans are out yet but we presume that it will be very competitive against Singtel's price plan. Starhub also has no put up any pre-order service. Starhub also promised to release their price plans by year end.
https://www.m1.com.sg/iPhone/preorder.jsp
