"I’m focused on giving the easiest experience to the user on all of his devices."

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"I’m focused on giving the easiest experience to the user on all of their devices."

Powers Gray offered a correction that might seem weird to a non-native speaker so I thought it might be helpful to get an explanation.

English doesn't have a non-gendered singular pronoun. You refer to people as either "he," or "she." People have historically defaulted to the masculine pronoun, but there's a movement to eliminate this.

The easiest way to eliminate the gendered pronoun is to do what Powers suggested and replace it with "they," or "their." This is technically grammatically incorrect, since you're talking about a single nongendered subject, but it's a very natural thing that native speakers do all the time.

I personally try to rewrite sentences such that you avoid the quirk altogether: "I'm focused on giving the easiest experience to every user on every device," or some such thing. This is probably one of the more difficult quirks of English right now, but it's good to be aware of because some people (including clients/employers!) care very passionately about it.

Sweet portfolio!