This is the 3585th most frequent Russian word.
смартфон
Smartphone.
Here, 'смартфон' is used as the direct object in the sentence, referring to the subject of the purchase.
Я купил новый смартфон.
I bought a new smartphone.
In this sentence, 'смартфон' acts as the subject in the comparative statement, being described in terms of its qualities.
Этот смартфон лучше предыдущего.
This smartphone is better than the previous one.
The word 'смартфон' is the object that fulfills the requirement in the sentence, denoting necessity for the task.