Elektronické podání přišlo datovou schránkou.

Here podání means something like submission, filing, or application/document that has been submitted.

It comes from the verb podat, which often means to submit or to file in official or administrative language.

So elektronické podání is not just any random electronic thing — it specifically means an officially submitted item in electronic form.

Because it has to agree with podání.

Podání is:

• singular
• neuter
• nominative here

So the adjective must also be:

• singular
• neuter
• nominative

That gives elektronické podání.

Compare:

• elektronický dokument = masculine
• elektronická žádost = feminine
• elektronické podání = neuter

This is standard adjective-noun agreement in Czech.

Yes. The verb agrees with the subject, and the subject here is podání, which is neuter singular.

So in the past tense:

• masculine: přišel
• feminine: přišla
• neuter: přišlo

Because podání is neuter, Czech uses přišlo.

It is the past-tense form of přijít.

Přijít usually means:

• to come
• to arrive
• sometimes to be received, depending on context

In official or administrative language, Czech often uses přijít where English might prefer arrive, come in, or even be received.

So in this sentence, přišlo means that the submission arrived or was received.

It is in the instrumental singular.

The dictionary form is datová schránka.
In the instrumental singular, that becomes datovou schránkou.

This case is used here to express the means or method by which something came:

• datovou schránkou = by means of a data box
• more naturally in English: via a data box

Because Czech can use the instrumental case by itself to express the means by which something happens.

So:

• přišlo datovou schránkou = it came via / by means of a data box

This is similar to other examples:

• Poslal to e-mailem. = He sent it by email.
• Jela vlakem. = She went by train.
• Napsal to rukou. = He wrote it by hand.

So datovou schránkou is functioning like e-mailem or vlakem: it tells you the channel or method.

A datová schránka is a specific Czech administrative term. It is an official electronic mailbox used for communication with public authorities and, in some cases, between legal entities and other bodies.

So this is not just any mailbox or inbox. It refers to a formal government-recognized system for delivering official documents electronically.

That is why the sentence sounds bureaucratic or administrative.

The sentence has a normal, neutral word order:

• Elektronické podání = subject
• přišlo = verb
• datovou schránkou = means/method

Czech word order is flexible, so other versions are possible, for example:

• Datovou schránkou přišlo elektronické podání.
• Elektronické podání datovou schránkou přišlo.

But those alternatives shift the emphasis. The original sentence is the most neutral and natural if you are simply stating the fact.

Yes, depending on the exact nuance.

For example:

• bylo doručeno = was delivered
• došlo = was received / came in
• přišlo = arrived / came

But these are not always perfectly interchangeable.
Přišlo is quite natural for saying that something came in through a certain channel.
Bylo doručeno sounds more formal and focuses on successful delivery.
Došlo can also sound administrative, often in the sense of was received.

So přišlo is a natural choice here, but other official-style alternatives are possible in different contexts.