Sound and Features
Consistent with phones from its time, the Siemens C25 does not include a loudspeaker or a 3.5mm headphone jack. However, it supports monophonic ringtones and has a composer allowing users to create their own alerts. This feature provided a degree of customization that was both innovative and popular in its day. A highlight was its simplicity and ease of use in setting up personalized alarms despite the lack of a dedicated alarm feature.