The issue has apparently affected a 'disproportionate' number of Orange UK Hero users, according to multiple forum posts.
It seems the problem is to do with certain apps, mostly paid for versions, being copy protected to prevent piracy. These apparently don't show up on unlocked or developer handsets searching through the Market.
However, it appears the problem has cropped up on the recently released Orange Hero handsets too, with full versions of games like 'Robo Defense' available for trial but not for full purchase, despite being similarly available on the T-Mobile G1 and HTC Magic.
Some believe this issue is to do with the fact T-Mobile and Vodafone (the UK carrier of the Magic) are in the Open Handset Alliance behind Android, while Orange is currently still to join.
TechRadar has spoken to Orange, and it appears the phones are 'acting' like unlocked or developer versions, something the network is fixing:
"Further to recent reports of missing "Copy protected" applications on the HTC Hero in the UK, Orange can confirm thatit isaware of the issues andis working with HTC to urgently resolve.
"The Application visibility issue is entirely unrelated to membership of the OHA, as has been suggested.
"As itcurrently appears to be a server fix no change to handsets should be required, and once resolved we expect all paid applications in the English language to reappear."
Orange says it has started to fix the problem and apps have started to appear, and it hopes things will start to improve quickly.
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Gareth has been part of the consumer technology world in a career spanning three decades. He started life as a staff writer on the fledgling TechRadar, and has grown with the site (primarily as phones, tablets and wearables editor) until becoming Global Editor in Chief in 2018. Gareth has written over 4,000 articles for TechRadar, has contributed expert insight to a number of other publications, chaired panels on zeitgeist technologies, presented at the Gadget Show Live as well as representing the brand on TV and radio for multiple channels including Sky, BBC, ITV and Al-Jazeera. Passionate about fitness, he can bore anyone rigid about stress management, sleep tracking, heart rate variance as well as bemoaning something about the latest iPhone, Galaxy or OLED TV.