There are a number of options for students to use when choosing to submit a college application.  Although the process has become simplified over the years, there are still several options to consider when deciding which application is the most relevant.

Current application services include the Common Application, the Coalition Application, the Universal Application and, for students applying to the University of California System, the University of California Application.

Here is a primer on each service:

The Common Application

The Common Application (informally known as the Common App) is an undergraduate college admission application that applicants may use to apply to any of more than 800 member colleges and universities in 49 states and the District of Columbia, as well as in Canada, China, and many European countries.[1] Member colleges and universities that accept the Common App are made up of over 100 public universities, 10 Historically Black Colleges and Universities, and over 250 institutions that do not require an application fee. It is managed by the staff of a not-for-profit membership association (The Common Application, Inc.) and governed by a 13-member volunteer Board of Directors drawn from the ranks of college admission deans and secondary school college counselors. Its mission is to promote access, equity, and integrity in the college admission process, which includes subjective factors gleaned from essays and recommendations alongside more objective criteria such as class rank.

(Source, Wikipedia).

The Coalition Application

The Coalition for College is a diverse group of more than 140 distinguished colleges and universities across the U.S. that is committed to making college a reality for all high school students through its set of free, online college planning tools that helps them learn about, prepare for, and apply to college.

The Coalition’s online toolkit, MyCoalition, is designed to engage students in the college application process early and easily. It is comprised of a convenient digital storage Locker, interactive Collaboration Space, and easy-to-use application, which is accepted at all member schools.

The Coalition was founded by a group of dedicated college administrators in 2015 with the goal to improve the college application process for all students, particularly those from historically under-represented groups. Members are united in their mission to support lower-income, under-resourced, and/or first-generation students; provide responsible financial aid; and bolster students’ success in college—and beyond.

(Source, The Coalition Application, FAQ). 

The Universal Application

The for-profit Universal College Application is accepted by 34[1] higher education institutions in the United States (as of December 2016). It was started in 2007.[2] Varied numbers of institutions accept this application; 77 used the service in 2010.[2] In addition to the Universal College Application, a school may have its own application materials. The Universal College Application was created for use by any size or type of higher education institution.

One intention of the Universal College Application is to save time and work for students by letting them submit the same application to any of the participating colleges. This is similar to the more popular Common Application, the Universal College Application's main competitor. Most of the schools participating in the Universal College Application also accept the Common Application.[2][3]

Unlike some of its competitors, the Universal College Application does not try to reflect a certain educational philosophy.[2][3] Besides fees, the Universal College Application's only demand for schools to participate is for them to be accredited and uphold the National Association for College Admission Counseling's Statement of Principles of Good Practice.

(Source, Wikipedia). 

The University of California Application

If you are interested in applying to one or all of the nine colleges that are part of the University of California system, this is the application to use.  Whether you are in state, a California resident, or a transfer student, the UC Application provides a single source tool to apply.