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README.md

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+========================================================
+   THE 974-BYTE ANDROID APP  —  how I got this small
+========================================================
+
+I built a real, working Android app that is only 974 bytes.
+For comparison, a single short text message is bigger than this
+whole app. It installs from a tap, shows a window on the screen,
+and runs on a normal, up-to-date phone.
+
+It is built for ANDROID 14 (also called "API level 34"), which
+is the current, fully modern version of Android. It is not aimed
+at some ancient phone to cheat the size down — it is set to
+Android 14 at BOTH ends: the oldest phone it allows AND the
+version it is built against are both Android 14. I tested it on
+a real Android 14 phone: it installed and opened with a window
+on screen. So this is a genuine, present-day 974-byte app, not a
+technicality that only works on outdated devices.
+
+The trick? I wrote the app by hand, byte by byte. Instead of
+using the usual tools that pad an app with lots of extra stuff,
+I placed every single byte myself and kept only what the phone
+absolutely refuses to live without.
+
+
+HOW I SHRANK IT (in plain terms)
+--------------------------------
+Think of the app as a tiny box with four things inside:
+
+  1. THE INSTRUCTIONS  — a note telling the phone what the app
+     is called and that it should show up on the home screen.
+     I trimmed this note down to the bare minimum wording.
+
+  2. THE CONTENTS       — normally an app carries its own code.
+     Mine carries none. I told the phone "borrow a window you
+     already have built in," so the app needs no code at all.
+     That removed a big chunk in one stroke.
+
+  3. THE SEAL           — every modern app must be sealed with a
+     tamper-proof signature so the phone trusts it. This seal is
+     mostly unavoidable math, but I used the smallest seal the
+     phone will still accept and stripped every optional scrap
+     of paperwork around it.
+
+  4. THE WRAPPER        — the "envelope" that holds it all
+     together. I removed every field the phone doesn't actually
+     read, and kept only the ones it checks.
+
+I tested every single cut on a real phone. If the phone
+complained, I put the byte back. If it stayed happy, the byte
+was gone for good. I did this hundreds of times until nothing
+else could come out without the phone rejecting the app.
+
+
+THE CLEVER FINAL TRICK
+----------------------
+The app needs to point at a "window" to display. Normally you'd
+write out a long name for that window. Instead, I gave my app a
+name that lets it borrow the phone's OWN built-in window using a
+tiny shorthand — like signing a letter "-J." instead of your
+full name because the reader already knows who you are.
+
+
+CAN IT GO EVEN SMALLER?
+-----------------------
+Yes — but with a trade-off.
+
+This 974-byte app is locked to Android 14 (API 34). That choice
+COSTS bytes, on purpose, so the result is honestly modern.
+
+A big part of what's left is the SEAL, and a big part of the
+seal's size comes from a rule on today's phones: it must use a
+fairly strong lock. Older versions of Android allowed a smaller,
+weaker lock. If you aim the app at an OLDER Android version, the
+phone accepts that smaller seal — and the app gets smaller.
+
+The same goes for a few of the phone's safety rules I had to
+satisfy. Newer Android is stricter (more required bytes); older
+Android is more relaxed (fewer required bytes). A few concrete
+examples of where the version line changes things:
+
+  - Android 12 (API 31) and up FORCES an extra "can other apps
+    open this?" setting to be spelled out. Below that, it's
+    optional — so aiming lower drops it and saves bytes.
+
+  - Older Android accepts a weaker signing lock, which is
+    physically smaller than the one Android 14 demands.
+
+So:
+
+    Want it EVEN smaller?  ->  Aim at an older Android (e.g.
+                               API 30 or below) and drop the
+                               stricter, bigger requirements.
+
+    Want it fully modern?  ->  Aim at Android 14 (API 34) and
+                               pay a few more bytes, like mine.
+
+I chose to keep it fully modern — Android 14, today's phones,
+today's security — and it still fits in 974 bytes.
+
+
+THE BOTTOM LINE
+---------------
+I hand-placed 974 bytes. Every one of them is either something
+the phone genuinely requires, or squeezed down as far as it can
+go. It installs, it opens, it shows on screen — a complete app,
+smaller than the words on this page.
+========================================================