Learn Hardcore Russian: Включи лампочку на устройстве через приложение. - Turn on the bulb on the device using the application.

включи is the second-person singular imperative of the perfective verb включить. It literally means turn on and is used to give a direct command to one person. Because it’s perfective, it asks for the action to be completed. The stress falls on the last syllable: vkluch-EE.

Why is лампочку used instead of лампочка, and what case is it?

лампочку is the accusative singular form of лампочка (light bulb). It appears in the accusative because it’s the direct object of включи. Feminine nouns ending in -а or -я always change their ending to -у or -ю in the accusative singular.

What case is на устройстве, and why do we use it here?

устройстве is in the prepositional case, marked by the ending -е. When combined with the preposition на, it indicates location (“on the device”). So на устройстве means “on the device.”

Why is через приложение used, and why is приложение in the accusative?

The preposition через (“through, via”) always requires the accusative case. приложение is a neuter noun whose nominative and accusative singular forms are identical, so it stays приложение.

Could you say в приложении instead of через приложение, and what’s the difference?

Yes. в приложении (в + prepositional) also means “in the app,” focusing on location inside the app interface. через приложение (через + accusative) emphasizes using the app as the channel or tool to perform the action.

What’s the difference between the imperatives включи and включай?

включи is the perfective imperative (one-time, complete action: “turn on (once)”).
включай is the imperfective imperative, used for ongoing or repeated actions (e.g. “keep turning on” or “start turning on, repeatedly”).

How flexible is the word order in this sentence? Could parts be rearranged?

Russian word order is fairly flexible. The basic meaning stays the same if you say, for example, Через приложение включи лампочку на устройстве, but that shifts the emphasis onto через приложение. In the original order—Лампочку на устройстве через приложение—you present object → location → tool in a neutral sequence.

How would you specify “your device” if you wanted to say “turn on the light on your device through the app”?

You’d insert a possessive pronoun in the prepositional case to match устройстве.
Informal singular: Включи лампочку на твоём устройстве через приложение.
Formal or plural: Включите лампочку на вашем устройстве через приложение.