Con VB6.0 non puoi sviluppare applicazioni Mobile.
Ci vuole eMbedded Visual Basic 3.0 ma ormai anche questo è diventato un ambiente obsoleto, come afferma Microsoft qui:
http://msdn.microsoft.com/it-it/library/ms838188(en-us).aspx?ppud=4

eMbedded Visual Basic 3.0
Developers cannot use eMbedded Visual Basic to develop applications for Windows Mobile 2002-based Smartphone or Windows Mobile 5.0-based devices. Due to this and other factors, including the strong interest in the development community about Visual Basic .NET, the eMbedded Visual Basic technology has been phased out and replaced by the more powerful Visual Basic .NET language. Microsoft recommends that developers use Visual Basic .NET to create all new Pocket PC applications and use eMbedded Visual Basic for maintaining older applications for legacy devices.