Best chess software?

Hi - my rating is consistently around 1400-1500, and I can't seem to improve much. I would like to buy some chess software for doing tactics and such - however, I have NO CLUE what to look for. I've heard about Chessmaster, Fritz, CT Art, but don't know anything about them.

The free tactics on here and chesstempo are quite limited, and it's frustrating for me to not be able to track my progress.

The chesstempo, or tactics trainer, or the lichess trainer (my favorite, but it's almost identical to the others) are better than all the programs you have listed. 

CT-ART in particular got really bad after the 'upgrades' to the interface a few years ago - it's literally almost unusable now since it's so clunky. 

The web tactics resources are so good- just do a lot of 'em. If you're playing a lot of blitz, set them to 'easier' type settings (you can do that in lichess) to drill your faster pattern recognition and blunder avoidance, and if you're playing more longer games, set them to 'normal' or 'harder' to get deeper problems.

I've tried everything - books, websites, CT-ART and other software, .pgn tactics, and while none of them are 'bad' (except CT-ART's interface now), the online tactics trainers are the ones I've gotten the best results with. 

Thanks for the advice. So is the free version of lichess enough, or do I have to buy anything if I want to become good - really good?

Also, what about the chess.com features like chess mentor? Is that any good for a player like me?

Remember, that tactics, while critical to good play, is only tactics. 

At a fairly low level (for example, around my ratings level of 1400 blitz here on chess.com, which are higher than standard ratings), you will need a lot more than tactics to win games since your opponents won't blunder much unless you put strategic pressure on them and force them into blundering situations. 

lichess is free. I've heard good things about chess mentor - someone else can comment on it. 

I do think you'll make fastest progress by studying mostly tactics for awhile until you notice you're not losing many games because of few-move tactical combos.

Actaully the reason I lose the majority of times is not because I missed some tactical combination, but rather, I have no clue what to do in the end-game. Basically, I get worse and worse the less pieces there are on the board. I have no idea how to work around this...

I have Silman's Complete Endgame Manual, which is great, but it focuses on how to mate with, say, 2 rooks vs 1 king. It doesn't say what I should do with 2 knights and a bishop vs his 2 rooks and knight, for example. I just don't know how which squares I should go to etc.