What web-based trading platform do you prefer?

Hi!
Recently, I tried to use and test a couple of web trading apps. I got interested in them because they don't require installation and I can use it on my Mac. I respected to get speed and the ability of active trading performing. But only some of them showed me good results.
Do you use web trading apps? And what features do you value the most in them?

Waiting for your answers

No, because I run my own stuff.
In general their legitimate purpose is to be able to run anywhere/on any hardware that provides the bare minimum, i.e. browser.

Have tried any web trading app? and what stuff do you mean?

I think so: i.e. LMAX, OandA, also Dukascopy's just for fun and other exotic brokers' stuff.
I made my own terminal. I use MT4 only to pull data and channel orders through it. Because I find I cannot trade well with apps that brokers provide, because by their nature they are generic, and made mostly for trading on higher time frames where it does not matter if you leave a few pips here and there (because of the redundant tasks), because then you not aim for just those few pips anyway.. So I needed a platform that is extermely steamlined to my personal needs.. so I had to do my own.