An assumption, not a feature
On a supported iPhone, dictation processes speech on the device itself. It needs no Apple ID, it works with no connection, and it is simply there in the keyboard without being configured.
Almost nobody notices any of that while it is true, because nothing draws attention to it. It is only afterwards, on a different platform, that the absence becomes obvious: dictation that stalls on a train, or wants a connection, or behaves differently depending on which handset you bought.
So what you are missing is not a feature you could point at in a list. It is an assumption. Speech is handled on the phone, it works without a signal, and it asks nothing of you. On Android that assumption has to be chosen rather than inherited, and choosing it takes a few minutes and costs something.
Android’s starting position
The keyboard your Android phone came with almost certainly has voice typing, and on many handsets an offline language pack can be downloaded so it keeps working without a connection. For a lot of people that is enough and nothing further is required.
The difference from what you had is that local processing is one mode among others, not the design of the thing. Whether it applies depends on your handset, your language and whether the right pack is installed, and it can change with an update.
If what you actually valued was not having to think about it, a mode you have to verify is not the same thing.
Verifying it takes half a minute, for what it is worth. Put the phone in airplane mode, open a notes app, and dictate a sentence. Whatever happens next is the real answer for your handset and your language, and it is a better test than any support page.
Where LocalType comes in
LocalType is an Android keyboard where the recognition runs on the phone, and there is no other path in the app at all. No cloud mode exists to fall back to and no setting governs it.
Practically it behaves the way you expect: the microphone is a key on the keyboard, the text lands in whatever field you were already in, nothing is copied and the clipboard is untouched. It works anywhere a keyboard opens, on phones and tablets running Android 8.0 and newer.
Nothing needs signing into, so no identity of any kind is attached to your keyboard. The product carries no advertising and nothing inside it keeps a record of how you use it. There is no store of your recordings to worry about, since the sound becomes text and then stops existing. The model file lives where only this app can reach it, and Android's routine cloud backup is deliberately denied the app's data. Move to a password box and the microphone key is simply absent. The only outward connection the app ever makes is the one that collects the speech model you selected.
Away from the microphone it behaves as a keyboard should: autocorrect and next-word suggestions from a dictionary matched to your language, the standard layouts including the German and French arrangements where those are expected, a full emoji set, and room to add your own names and jargon.
The setup, which takes five minutes
Android puts two steps in front of a new keyboard, not one, and this catches out almost everyone arriving from iOS.
Installing is not enough. You enable the keyboard in Android's language and input settings, which shows a warning that appears for every keyboard including the one your phone shipped with, and then you select it from the keyboard selector that appears when a text field is open.
After that, one extra step for dictation: choose and download a speech model inside the app, and grant microphone permission the first time you use the key. Do the download on Wi-Fi before you need it, because the model is between 60 and 539 MB depending on which one you pick.
Your previous keyboard stays enabled throughout, so switching back mid-sentence is one tap from the same selector. Nothing about this is a commitment, and the sensible way to test it is a week of ordinary messages rather than an afternoon of deliberate trials.
Moving between languages without a menu
If you write in more than one language, this is the part that will feel familiar.
LocalType covers eighteen languages with a single multilingual model and works out which one you are speaking from the recording rather than from a menu, so moving between them between messages needs nothing from you. Reply to your mother in one language and your landlord in another and no setting changes in between. Pin it to a specific language instead and the layout, the dictionary and the dictation language move together.
Accuracy is not identical across those eighteen, because training material is not. Widely spoken languages come out best, which is true of every speech model on every platform.
What you lose
Two things you had and will not have, and one consequence of the design.
It is a separate app you install and pay for after a trial, not something built into the system. That means an install, a download and a decision, none of which were required before.
It is a keyboard, where iOS gave you a system-wide service, so it works where a keyboard works. That covers nearly everything you type into, and it is not identical to a feature woven into the operating system.
And nothing is restored to a new phone. Because the app's data is kept out of cloud backup, moving handsets means installing and downloading a model again, and rebuilding the words you added. Nothing about your vocabulary is stored off the device, and this follows directly from that. It is a trade, and not an oversight.
Gains, on the other side of the ledger
Two things arrive that you did not have before, and better found in the first week than in the second year.
You can teach it your vocabulary. Names, places, jargon and acronyms can be added by hand, and those additions stay on the handset and are handed to the speech model as context, so they start arriving spelled correctly. For anyone whose writing is full of proper nouns, this is the one setting that changes results rather than trading one thing for another, and it is worth ten minutes on the first day.
You can choose how hard the phone works. LocalType ships three models, at 60, 190 and 539 MB, trading speed against accuracy. iOS made that decision for you. For a sense of scale, the 190 MB middle setting needed 4.1 seconds to write out 6.9 seconds of talking on the 4 GB phone used for testing, and the biggest one roughly doubles the time you spent speaking. A smaller one on an older handset, a larger one if you dictate in noisy places, and only one of them is kept on the device at a time, so trying the others costs nothing but the download.
Both are things people notice when they go back the other way, which matters if you were expecting the move to be all losses.