diff --git a/hardware-concurrency/index.d.ts b/hardware-concurrency/index.d.ts
new file mode 100644
index 0000000..c5d2587
--- /dev/null
+++ b/hardware-concurrency/index.d.ts
@@ -0,0 +1 @@
+export function useHardwareConcurrency(): { unsupported: true } | { unsupported: false, numberOfLogicalProcessors: number }
diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..dedf30a
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,4 @@
+export * from './hardware-concurrency'
+export * from './memory'
+export * from './network'
+export * from './save-data'
diff --git a/memory/index.d.ts b/memory/index.d.ts
new file mode 100644
index 0000000..0c947e8
--- /dev/null
+++ b/memory/index.d.ts
@@ -0,0 +1,10 @@
+export interface MemoryStatus {
+  deviceMemory: number,
+  totalJSHeapSize: number | null,
+  usedJSHeapSize: number | null,
+  jsHeapSizeLimit: number | null
+}
+
+export function useMemoryStatus(initialMemoryStatus?: MemoryStatus): { unsupported: true } & Partial<MemoryStatus> |  {
+  unsupported: false,
+} & MemoryStatus
diff --git a/network/index.d.ts b/network/index.d.ts
new file mode 100644
index 0000000..bafa128
--- /dev/null
+++ b/network/index.d.ts
@@ -0,0 +1,6 @@
+export type EffectiveConnectionType = 'slow-2g' | '2g' | '3g' | '4g'
+
+export function useNetworkStatus(initialEffectiveConnectionType?: EffectiveConnectionType | null): {
+  unsupported: boolean,
+  effectiveConnectionType: EffectiveConnectionType | null
+}
diff --git a/package.json b/package.json
index 895ae56..e422baf 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,9 @@
   "main": "dist/index.js",
   "module": "dist/index.module.js",
   "unpkg": "dist/index.umd.js",
+  "typings": "index.d.ts",
   "source": "index.js",
+  "typings": "index.d.ts",
   "scripts": {
     "build": "microbundle",
     "dev": "microbundle watch",
@@ -35,4 +37,4 @@
     "react",
     "performance"
   ]
-}
\ No newline at end of file
+}
diff --git a/save-data/index.d.ts b/save-data/index.d.ts
new file mode 100644
index 0000000..9b6eb18
--- /dev/null
+++ b/save-data/index.d.ts
@@ -0,0 +1 @@
+export function useSaveData(initialSaveDataStatus?: boolean | null): { unsupported: boolean, saveData: boolean | null }