diff --git a/.gitignore b/.gitignore
index c7b5ece..380f3ba 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,6 +6,5 @@ Thumbs.db*
 ~*
 
 platform
-provider
 *.js
 *.d.ts
\ No newline at end of file
diff --git a/src/provider.ts b/src/provider.ts
index 5b7f556..d369f51 100644
--- a/src/provider.ts
+++ b/src/provider.ts
@@ -9,10 +9,11 @@ export interface IOAuthOptions {
     redirectUri?: string;
     responseType?: string;
     state?: string;
+    excludeRedirectUri?: boolean
 }
 
 const DEFAULTS = {
-  redirectUri: 'http://localhost/callback'
+    redirectUri: 'http://localhost/callback'
 };
 
 export class OAuthProvider implements IOauthProvider {
@@ -30,25 +31,29 @@ export class OAuthProvider implements IOauthProvider {
     }
 
     parseResponseInUrl(url) {
-      const response = utils.parseQueryString(url);
+        const response = utils.parseQueryString(url);
 
-      if (!this.isValid(response)) {
-        const error = new Error(`Problem authenticating with ${this.name}`);
+        if (!this.isValid(response)) {
+            const error = new Error(`Problem authenticating with ${this.name}`);
 
-        Object.defineProperty(error, 'response', { value: response });
-        throw error;
-      }
+            Object.defineProperty(error, 'response', { value: response });
+            throw error;
+        }
 
-      return response;
+        return response;
     }
 
     dialogUrl() {
-      return this.optionsToDialogUrl(this.options);
+        return this.optionsToDialogUrl(this.options);
     }
 
     protected optionsToDialogUrl(options: any): string {
         utils.defaults(options, this.defaults)
-        let url = `${this.authUrl}?client_id=${options.clientId}&redirect_uri=${options.redirectUri}`;
+        let url = `${this.authUrl}?client_id=${options.clientId}`;
+
+        if (!options.excludeRedirectUri) {
+            url += "&redirect_uri=" + options.redirectUri;
+        }
 
         if (options.appScope) {
             url += `&scope=${this.serializeAppScope(options.appScope)}`;
@@ -66,7 +71,7 @@ export class OAuthProvider implements IOauthProvider {
     }
 
     protected serializeAppScope(scope) {
-      return typeof scope.join === 'function' ? scope.join(this.APP_SCOPE_DELIMITER) : scope;
+        return typeof scope.join === 'function' ? scope.join(this.APP_SCOPE_DELIMITER) : scope;
     }
 
     protected isValid(response) {
diff --git a/src/provider/fitbit.ts b/src/provider/fitbit.ts
new file mode 100644
index 0000000..11c939c
--- /dev/null
+++ b/src/provider/fitbit.ts
@@ -0,0 +1,12 @@
+import { OAuthProvider, IOAuthOptions } from "../provider";
+
+export class Fitbit extends OAuthProvider {
+
+  constructor(options?: IOAuthOptions) {
+    super(options);
+    this.authUrl = 'https://www.fitbit.com/oauth2/authorize';
+    this.defaults = {
+      responseType: 'code'
+    };
+  }
+}
diff --git a/src/provider/polar.ts b/src/provider/polar.ts
new file mode 100644
index 0000000..3e2fc93
--- /dev/null
+++ b/src/provider/polar.ts
@@ -0,0 +1,13 @@
+import { OAuthProvider, IOAuthOptions } from "../provider";
+
+export class Polar extends OAuthProvider {
+
+  constructor(options?: IOAuthOptions) {
+    super(options);
+    this.authUrl = 'https://flow.polar.com/oauth2/authorization';
+    this.defaults = {
+      responseType: 'code',
+      excludeRedirectUri: true
+    };
+  }
+}
diff --git a/src/provider/runkeeper.ts b/src/provider/runkeeper.ts
new file mode 100644
index 0000000..bc20ba1
--- /dev/null
+++ b/src/provider/runkeeper.ts
@@ -0,0 +1,12 @@
+import { OAuthProvider, IOAuthOptions } from "../provider";
+
+export class Runkeeper extends OAuthProvider {
+
+  constructor(options?: IOAuthOptions) {
+    super(options);
+    this.authUrl = 'https://runkeeper.com/apps/authorize';
+    this.defaults = {
+      responseType: 'code'
+    };
+  }
+}