A Californian woman has filed a class action against Apple after switching to an Android phone and finding that text messages sent by friends with iPhones didn't reach her.



The reason for the non-delivery was that her phone number was still linked to an iPhone in Apple's system, and so it tried to deliver the texts using its proprietary data-channel "iMessage", which gets around the 160-character limits of standard SMS messages.

Adrienne Moore filed a complaint in San Jose, California, on 15 May, alleging that people who replace Apple devices with non-Apple phones or tablets are "penalised and unable to obtain the full benefits of their wireless-services contracts". She is seeking damages of up to $5m. That could be increased if other complainants join the action and it is successful.

Moore complained that Apple retains the text messages sent from other iPhone users to her and won't deliver them to the Samsung Galaxy S5 that she now uses. She complains in the suit that Apple failed to disclose that switching to a device other than one running its own software would cause the interference with delivery, and that this therefore constitutes interference with her contract with her mobile carrier, and unfair competition.

Apple's iMessage, introduced in October 2011 at the same time as its iPhone 4S phone, is an opt-in service provided on iPhones, iPads, iPods and Apple computers which lets users link a particular email address or phone number to the service. It lets them send messages of arbitrary sizes to other users of the iMessage service. It has become widely used by Apple device owners, with more than 450bn iMessages being sent by April 2013, and more than 2bn messages being sent daily at that time.

But some iPhone users who have switched to other platforms have discovered that friends who remain on Apple's platform keep sending them iMessages, but that they never arrive.

This is because when iMessage is activated on an iPhone, it associates the phone number with the service. If the user retains their phone number but switches to a different platform such as Google's Android or Microsoft's Windows Phone, Apple's system tries to deliver the message to the phone number, but the software on the other platforms cannot accept the message.

Apple also seems to keep iMessage active and associated with a phone number if it is being used with other Apple devices.

Moore used an iPhone 4 until 16 April, when she switched to the Galaxy S5 on Verizon's service. The carrier told her that in order to receive messages as before she should turn off iMessage on the old phone - but she says that even after doing so she still doesn't receive all messages sent to her from other iPhones.

Moore complains that Apple's suggested fixes – that people using older versions of iOS to contact her should update, and that people using iPhones should delete and re-add her as a contact – were either impractical or didn't work.

According to Patently Apple, which has a copy of the complaint, Moore says that "Had Plaintiff and the class members been informed by Apple that iMessage would work in such a fashion so as to prevent them from receiving text messages, once they switched their Apple devices to non-Apple devices, Plaintiff and the putative class members would not have downloaded the iMessage and Messages service and application, or would not have purchased an iPhone or other Apple device in the first instance."

Apple declined to comment on the lawsuit.

• Apple provides an advice page for people who are moving to other platforms about how to deactivate iMessage.

• Samsung also provides an advice page for people who are moving away from the iPhone about how to turn off iMessage before switching to their new device.

• Adam Pash, who says he is in "iMessage purgatory" in the same fashion as Moore claims to be in the lawsuit, says that one fix is for would-be senders of messages to people who were using iPhones to turn off iMessage, send a text to the former iPhone user's number, and then turn iMessage back on. That seems to break the association between iMessage and the former user's number in Apple's system.

• Secure text message service Silent Circle revamps iOS app

