At the stroke of midnight, thousands of consumers will be the first in Hong Kong to obtain Apple's iPhone 4 for free or just HK$580. Those attractive options are being offered by mobile network operators 3 Hong Kong and SmarTone-Vodafone, which announced yesterday their respective tariff plans for the sleek, video-conferencing-ready smartphone. The two firms and new Apple carrier-partner CSL will each host iPhone 4 launch parties tonight where attendees will be able to buy the device on site instead of heading to the shops tomorrow. To get a free 16-gigabyte iPhone 4, subscribers must choose the HK$398 monthly plan that comes with unlimited data usage and intra-network text messaging. With its plan, 3 Hong Kong bundles 2,500 voice minutes per month - a bit more than the 2,400 that come with the comparable SmarTone-Vodafone package. A 32GB iPhone 4 is available with an upfront payment of HK$580 with that unlimited data plan. For iPad users, 3 Hong Kong is offering unlimited local data and Wi-fi links for an extra HK$50 a month to those on its HK$398 iPhone plan. The cheapest plan for both carriers costs HK$138 a month, with 100 megabytes of data and unlimited intra-network text messaging. With this plan, a 16GB iPhone 4 is offered at HK$3,480 by SmarTone-Vodafone and HK$3,380 by 3 Hong Kong. The handset's 32GB version under the same monthly plan will cost HK$4,280 with SmarTone-Vodafone and HK$4,180 with 3 Hong Kong. Calls made to CSL, the city's largest wireless network operator, about its iPhone 4 tariff plan were not returned yesterday. CSL chief executive Joseph O'Konek had earlier said selected 1010 and one2free shops would remain open at midnight to accommodate preregistered customers not invited to the carrier's launch party. Stephen Chau Kam-kun, SmarTone-Vodafone's chief technology officer, said the operator had stock reserved to cover all 2,000 invited guests at its event at the IFC Mall in Central. 'Despite the publicity about the iPhone 4's antenna issues, the demand is huge,' Chau said. However, he declined to say how many customers had preregistered to buy the device. PCCW Mobile, which is not an Apple carrier-partner, introduced yesterday rebate offers of up to HK$4,988 for customers who use its concierge service to order an iPhone 4 from authorised dealers and shops.