This year has seen a substantial increase in the number of colleges offering mobile apps for campus resources and services. But the use of Web-based services, known as ?the cloud,? for administrative services is growing slowly, according to a national survey of campus-technology leaders.Only 37.1 percent of the 496 colleges that responded to the survey reported that they did not have a mobile app and were neither planning for one for this academic year nor reviewing one for the future, the Campus Computing Project found.