Trademark law in a nutshell
Good Phorm have taken the trouble to register their trademark and have used the little R symbol. This gives them quite a lot of protection under the law - with one proviso (see below)
Bad Phorm have chosen to use the weaker TM on their logo. Anyone who wants to assert a trademark can include the TM. It does not need to be registered and no money changes hands. HOWEVER in exchange for being cheap, courts are unlikely to be sympathetic when that trademark comes into conflict with a registered mark.
There's an obvious risk of confusion - 'Phorm' is not a word in the dictionary (which is one defence out of the window - you could start a company called Apple and still be protected) and both companies are in the Internet business (which would be a problem if your Apple startup was a computer company).
If I was Good Phorm, I'd love to know how Bad Phorm can claim to have independently hit upon their logo design - right down to the font. That takes coincidence too far.
So the name and the logo of Bad Phorm could, and should, be seen as a case of 'passing off'.
Actually Good Phorm *MUST* defend their trademark. If they choose not to do so in this case, their mark is in danger of become genericised, in which case *anyone* can use it. Good Phorm need to talk to their lawyers as a matter of urgency and get them issue a cease and desist order against Bad Phorm ordering them withdraw their logo and cease trading under that name.
Bad Phorm can claim an innocent error, even blame their designers who may be liable for any costs of infringement. In any case it'd make sense for them to withdraw the logo and the name as they'd almost certainly lose in court.
And if Good Phorm they need money, I'm willing to throw in a £20 to the Register defence fund.