Latest refers to the most recent element in a chronological series, making it similar in meaning to newest. It is also the superlative form of the adjective late. Last refers to the final elements in any series. After the last element, there will be no more.
The finance department recently updated their computer systems and installed all the latest equipment.
Release 2.0 of the program was late. Release 3.2 was even later. But release 1.01 was the latest of all.
After this last release, there will be no more versions of the software.
The release will be the last.