He's always looking at his smart phone when he is awake.
Whenever he's not sleeping, he's always checking out his phone.
ーHe's always looking at his smart phone when he is awake.
「彼は起きている時、いつもスマホを見ている」
to look at one's smart phone で「スマホを見る」
when he is awake で「起きている時」
ーWhenever he's not sleeping, he's always checking out his phone.
「彼は寝ていない時は、いつも携帯をチェックしている」
whenever he's not sleeping で「彼は寝ていない時はいつも」＝「起きている時はいつも」
to check out one's phone で「携帯をチェックする」
ご参考まで！
As soon as he wakes up, the first thing he does is stare at his phone.
From the moment he wakes up his eyes are glued to his phone at all times.
ご質問ありがとうございます。
「彼は起きているときはいつもスマホを見ている」は英語で「As soon as he wakes up, the first thing he does is stare at his phone.」と言えます。
別の言い方ですが、少し大袈裟で「From the moment he wakes up his eyes are glued to his phone at all times.」と言えます。これで彼の目は接着剤で携帯に接着されている状態です。もちろん、大袈裟ですが、言いたいことは携帯は見すぎと伝えられます。
ご参考になれば幸いです。
カナダ 
アメリカ合衆国 
