Better way to find index of item from ArrayList<CustomObject>

You can use list.indexOf(), but in order to make it work, you need to override equals and hasCode of your POJO.

By default, two objects will be considered equal if they have the same reference. You can overwrite equals to work for your case:

public boolean equals(Object o) {
  if (!(o instanceof POJO)) {
    return false;
  }
  POJO other = (POJO) o;
  return name.equalsIgnoreCase(other.getName());
}

Overridding equals would suggest you override hashCode. For example:

public int hashCode() {
  return name.hashCode();
}

Finding element in this way where complexity would be give you BIG-O (n). I think if you Map that would gives you better result.

HashMap would be better choice. - Where Complexity would be O(1).

If you need to search on a string value you should use a HashMap instead of ArrayList.