Primer paso de la investigacion. Se aportan el .apk, las carpetas con el apk extraido y el apk descompilado. El archivo API_DOCUMENTATION.md es un archivo donde se anotaran los descubrimientos del funcionamiento de la API, y los .py son scripts para probar la funcionalidad de la API con los métodos que vayamos encontrando. Finalmente, los archivos .js son scripts de Frida para extraer informacion de la APP durante la ejecucion.

apk_decompiled/sources/kotlin/ranges/CharProgression.java

@@ -0,0 +1,107 @@
+package kotlin.ranges;
+
+import java.util.Iterator;
+import kotlin.Metadata;
+import kotlin.internal.ProgressionUtilKt;
+import kotlin.jvm.internal.DefaultConstructorMarker;
+import kotlin.jvm.internal.Intrinsics;
+import kotlin.jvm.internal.markers.KMappedMarker;
+
+@Metadata(d1 = {"\u00004\n\u0002\u0018\u0002\n\u0002\u0010\u001c\n\u0002\u0010\f\n\u0002\b\u0003\n\u0002\u0010\b\n\u0002\b\t\n\u0002\u0010\u000b\n\u0000\n\u0002\u0010\u0000\n\u0002\b\u0003\n\u0002\u0018\u0002\n\u0000\n\u0002\u0010\u000e\n\u0002\b\u0002\b\u0016\u0018\u0000 \u00192\b\u0012\u0004\u0012\u00020\u00020\u0001:\u0001\u0019B\u001f\b\u0000\u0012\u0006\u0010\u0003\u001a\u00020\u0002\u0012\u0006\u0010\u0004\u001a\u00020\u0002\u0012\u0006\u0010\u0005\u001a\u00020\u0006¢\u0006\u0002\u0010\u0007J\u0013\u0010\u000f\u001a\u00020\u00102\b\u0010\u0011\u001a\u0004\u0018\u00010\u0012H\u0096\u0002J\b\u0010\u0013\u001a\u00020\u0006H\u0016J\b\u0010\u0014\u001a\u00020\u0010H\u0016J\t\u0010\u0015\u001a\u00020\u0016H\u0096\u0002J\b\u0010\u0017\u001a\u00020\u0018H\u0016R\u0011\u0010\b\u001a\u00020\u0002¢\u0006\b\n\u0000\u001a\u0004\b\t\u0010\nR\u0011\u0010\u000b\u001a\u00020\u0002¢\u0006\b\n\u0000\u001a\u0004\b\f\u0010\nR\u0011\u0010\u0005\u001a\u00020\u0006¢\u0006\b\n\u0000\u001a\u0004\b\r\u0010\u000e¨\u0006\u001a"}, d2 = {"Lkotlin/ranges/CharProgression;", "", "", "start", "endInclusive", "step", "", "(CCI)V", "first", "getFirst", "()C", "last", "getLast", "getStep", "()I", "equals", "", "other", "", "hashCode", "isEmpty", "iterator", "Lkotlin/collections/CharIterator;", "toString", "", "Companion", "kotlin-stdlib"}, k = 1, mv = {1, 9, 0}, xi = 48)
+/* loaded from: classes3.dex */
+public class CharProgression implements Iterable<Character>, KMappedMarker {
+
+    /* renamed from: Companion, reason: from kotlin metadata */
+    public static final Companion INSTANCE = new Companion(null);
+    private final char first;
+    private final char last;
+    private final int step;
+
+    @Metadata(d1 = {"\u0000 \n\u0002\u0018\u0002\n\u0002\u0010\u0000\n\u0002\b\u0002\n\u0002\u0018\u0002\n\u0000\n\u0002\u0010\f\n\u0002\b\u0002\n\u0002\u0010\b\n\u0000\b\u0086\u0003\u0018\u00002\u00020\u0001B\u0007\b\u0002¢\u0006\u0002\u0010\u0002J\u001e\u0010\u0003\u001a\u00020\u00042\u0006\u0010\u0005\u001a\u00020\u00062\u0006\u0010\u0007\u001a\u00020\u00062\u0006\u0010\b\u001a\u00020\t¨\u0006\n"}, d2 = {"Lkotlin/ranges/CharProgression$Companion;", "", "()V", "fromClosedRange", "Lkotlin/ranges/CharProgression;", "rangeStart", "", "rangeEnd", "step", "", "kotlin-stdlib"}, k = 1, mv = {1, 9, 0}, xi = 48)
+    /* loaded from: classes3.dex */
+    public static final class Companion {
+        public /* synthetic */ Companion(DefaultConstructorMarker defaultConstructorMarker) {
+            this();
+        }
+
+        public final CharProgression fromClosedRange(char rangeStart, char rangeEnd, int step) {
+            return new CharProgression(rangeStart, rangeEnd, step);
+        }
+
+        private Companion() {
+        }
+    }
+
+    public CharProgression(char c4, char c5, int i) {
+        if (i == 0) {
+            throw new IllegalArgumentException("Step must be non-zero.");
+        }
+        if (i == Integer.MIN_VALUE) {
+            throw new IllegalArgumentException("Step must be greater than Int.MIN_VALUE to avoid overflow on negation.");
+        }
+        this.first = c4;
+        this.last = (char) ProgressionUtilKt.getProgressionLastElement((int) c4, (int) c5, i);
+        this.step = i;
+    }
+
+    public boolean equals(Object other) {
+        if (!(other instanceof CharProgression)) {
+            return false;
+        }
+        if (isEmpty() && ((CharProgression) other).isEmpty()) {
+            return true;
+        }
+        CharProgression charProgression = (CharProgression) other;
+        return this.first == charProgression.first && this.last == charProgression.last && this.step == charProgression.step;
+    }
+
+    public final char getFirst() {
+        return this.first;
+    }
+
+    public final char getLast() {
+        return this.last;
+    }
+
+    public final int getStep() {
+        return this.step;
+    }
+
+    public int hashCode() {
+        if (isEmpty()) {
+            return -1;
+        }
+        return (((this.first * 31) + this.last) * 31) + this.step;
+    }
+
+    public boolean isEmpty() {
+        return this.step > 0 ? Intrinsics.compare((int) this.first, (int) this.last) > 0 : Intrinsics.compare((int) this.first, (int) this.last) < 0;
+    }
+
+    public String toString() {
+        StringBuilder sb;
+        int i;
+        if (this.step > 0) {
+            sb = new StringBuilder();
+            sb.append(this.first);
+            sb.append("..");
+            sb.append(this.last);
+            sb.append(" step ");
+            i = this.step;
+        } else {
+            sb = new StringBuilder();
+            sb.append(this.first);
+            sb.append(" downTo ");
+            sb.append(this.last);
+            sb.append(" step ");
+            i = -this.step;
+        }
+        sb.append(i);
+        return sb.toString();
+    }
+
+    @Override // java.lang.Iterable
+    public Iterator<Character> iterator() {
+        return new CharProgressionIterator(this.first, this.last, this.step);
+    }
+}