An assistant is an assistant to a top manager (for example, a technical director or ROP), who is not yet a full-fledged loan, but at the expense of routine operations unloads his manager, and at the same time duplicates part of his functions.
Example. In each plank with a team of developers or manager there are routine things: delays, lack of reports, the simplest collection of feedback. These functions may well be taken over by the assistant, solving some problems, and, say, the feedback is processed by the manager (and decides what to do with it).
Front-end: $25
Back-end: $25 (PHP), $35 (JAVA, C#), $35 (Ruby, Python)
Analytics: $35 — $45
Mobile: $30
Design: $25 (designer), $35 (Art Director)
DevOps: $30
Testing: $20