Learn Hardcore Korean: aep seoljeongeuro gaeksil muni jadongeuro yeollige hal su isseoyo. - You can make the room door open automatically with the app settings.

-으로 here marks means/instrument: “by/with/through the app settings.”
Form rule: after a consonant (except ㄹ) use -으로; after a vowel or ㄹ, use -로. 설정 ends in the consonant ㅇ, so 설정으로 is correct.

Could I use 에서 or 을 통해 instead of 으로?

앱 설정에서 = “in the app settings” (location/context). Good when you mean “within the settings screen.”
앱 설정으로 = “by means of the app settings” (instrument). Emphasizes the means.
앱 설정을 통해 = “through the app settings.” Similar to -으로, a bit more formal or written. All are acceptable; choose by nuance.

Why is it 문이 and not 문을?

Because the verb is the passive/intransitive 열리다 “to open/be opened,” so the door is the subject:

문이 열려요 = “The door opens.”
문을 열어요 = “(I/you) open the door.” (active verb 열다)

What does -게 하다 do in 열리게 하다?

-게 turns the preceding clause into “so that …,” and 하다 adds “make/let.”
So 열리게 하다 = “make it so that (it) opens.” Structure: A/V-게 하다 = “to cause/allow A/V.”

Why not 열게 하다?

열게 하다 means “make/let someone open (it),” implying a person does the opening and the door is the object (문을). Here we’re causing the door itself to open (passively), so 문이 열리게 하다 is right.

What’s the difference between 열리게 하다 and 열리도록 하다?

They’re often interchangeable. -게 하다 is a bit more “make/let,” while -도록 하다 frames it as arranging/ensuring a result. In tech/UI copy, …열리도록 설정하다 sounds slightly more formal.

Could I say 문을 자동으로 열 수 있어요 here?

You can, but it shifts nuance to “you can open the door automatically (using the app/device),” focusing on your ability to perform the action.
To stress configuration, use e.g. 자동으로 열리게 설정할 수 있어요 or 자동으로 열리도록 설정할 수 있어요 (“you can set it to open automatically”).

What exactly does 자동으로 do? Can I use 자동 instead?

자동으로 is an adverb meaning “automatically,” modifying the verb 열리다. 자동 is a noun (“automatic”) and is used attributively in compounds, e.g. 자동 문 (“automatic door”), 자동 잠금 해제 (“auto unlock”). To modify a verb, keep 자동으로.

Is 앱 설정 singular or plural? Should I say 앱 설정들?

Korean doesn’t usually pluralize abstract/uncountable nouns. 앱 설정들 sounds unnatural. Just use 앱 설정 for “app settings.”

What’s the nuance of 객실 compared with 방?

객실 = “guestroom” in hotels/resorts, a formal/commercial setting.
방 = generic “room” in a house/building.
So 객실 문 is the door of a hotel room. For a home’s front door, use 현관문; for a bedroom door, 방 문/방문.

Should it be 객실 문 or 객실문?

Both appear. Compounds are often written solid (객실문), but spacing (객실 문) is also common and clear in UI text. Be consistent with your style guide. (Note: 방문 is a special case since it also means “visit.”)

Who is the implied subject in …할 수 있어요?

It’s typically “you” (the user), omitted because Korean often drops obvious subjects. If needed, you can add 사용자는 or 고객님은, but it’s usually unnecessary in UI/help text.

What politeness level is …있어요? When would …있습니다 be better?

…있어요: polite informal (standard for apps, help text, customer-facing copy).
…있습니다: polite formal (announcements, manuals, formal notices).
…있어: casual (friends).
Choose based on context and brand voice.

Is 앱 or 어플 better?

Use 앱. 어플 is colloquial and often discouraged in standard/professional writing.

How could I rewrite this to sound like natural app/UI copy?

A few options:

앱 설정에서 객실문 자동 열림을 설정할 수 있어요.
앱 설정에서 자동 열림을 켤 수 있어요.
앱 설정으로 객실문이 자동으로 열리도록 설정할 수 있어요.

What is 수 in 할 수 있어요?

수 is a bound noun meaning “way/possibility.” The pattern V-(으)ㄹ 수 있다 means “can/be able to V.” Here, 할 수 있어요 = “can do (it).”

Can I move 자동으로 or 앱 설정으로 around?

Word order is flexible, but keep modifiers close to what they modify:

Natural: 앱 설정에서 객실 문이 자동으로 열리게 설정할 수 있어요.
Natural: 앱에서 객실 문이 자동으로 열리도록 설정할 수 있어요. Avoid splitting 자동으로 far from 열리-, and avoid clunky repetitions like 앱 설정에서 … 설정할 수 있어요 unless your style guide prefers it.