Number of melodies
The number of melodies provided in the mobile. Numerous melodies makes the toy more interesting, but affects its value.
In mechanical models (see "Type"), there are usually only three melodies (if any). This gives some kind of variety, and it is difficult to foresee a larger number for technical reasons. In electric vehicles, this number may be higher, but the specific number varies. So, there are quite a few models that have only
five melodies or less ; and in the most advanced devices there can be
more than 20 melodies.
Operating time
The time during which the switched on mobile works before it turns off on its own. For mechanical models (see "Type"), this is actually the operating time in a full factory. Most often, it is about 10 minutes — for a longer work, a too bulky mechanism would be required, moreover, more time is not required so often. In electric models, the operating time is much longer — in the expectation that the parent will most likely turn off the device himself at the right time. And if the mobile is equipped with a timer (see "Features"), the operating time for it is indicated as the time after which the shutdown will occur if the timer is not set.
