After all and All together

After all adverb - In spite of expectations.

All together and after all are semantically related. In some cases you can use "All together" instead an adverb phrase "After all".

All together adverb - Used of a group whose members acted or were acted upon collectively and when `all' and `together' can be separated by other words.

After all and all together are semantically related. Sometimes you can replace phrase "After all" with "All together", this phrases are similar.