diff --git a/windowDetector/main.m b/windowDetector/windowDetector.h
similarity index 50%
rename from windowDetector/main.m
rename to windowDetector/windowDetector.h
index 7980e6f..d3122ba 100644
--- a/windowDetector/main.m
+++ b/windowDetector/windowDetector.h
@@ -1,5 +1,5 @@
 //
-//  main.m
+//  windowDetector.h
 //  windowDetector
 //
 //  Created by Jon Lara Trigo on 28/04/2020.
@@ -8,10 +8,10 @@
 
 #import <Foundation/Foundation.h>
 
-int main(int argc, const char * argv[]) {
-    @autoreleasepool {
-        // insert code here...
-        NSLog(@"Hello, World!");
-    }
-    return 0;
-}
+NS_ASSUME_NONNULL_BEGIN
+
+@interface windowDetector : NSObject
+
+@end
+
+NS_ASSUME_NONNULL_END
diff --git a/windowDetector/windowDetector.m b/windowDetector/windowDetector.m
new file mode 100644
index 0000000..491c3f4
--- /dev/null
+++ b/windowDetector/windowDetector.m
@@ -0,0 +1,58 @@
+//
+//  windowDetector.m
+//  windowDetector
+//
+//  Created by Jon Lara Trigo on 28/04/2020.
+//  Copyright © 2020 Jon Lara Trigo. All rights reserved.
+//
+
+#import "windowDetector.h"
+#import <Foundation/Foundation.h>
+#import <AppKit/AppKit.h>
+
+#define NSLog(FORMAT, ...) fprintf(stderr, "%s\n", [[NSString stringWithFormat:FORMAT, ##__VA_ARGS__] UTF8String]);
+
+@implementation windowDetector
+
+- (id) init
+    {
+    self = [super init];
+           if (!self)
+               return self;
+    [[[NSWorkspace sharedWorkspace] notificationCenter]
+     addObserver:self
+     selector:@selector(getInfo:)
+     name:NSWorkspaceDidActivateApplicationNotification
+     object:nil];
+        
+    [[[NSWorkspace sharedWorkspace] notificationCenter]
+     addObserver:self
+     selector:@selector(getInfo:)
+     name:NSWorkspaceDidTerminateApplicationNotification object:nil];
+
+    return self;
+    }
+
+- (void) getInfo:(NSNotification *)d
+    {
+    NSRunningApplication *app = d.userInfo[NSWorkspaceApplicationKey];
+
+    NSDate * now = [NSDate date];
+    NSDateFormatter *outputFormatter = [[NSDateFormatter alloc] init];
+    [outputFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
+    NSString *dateString = [outputFormatter stringFromDate:now];
+
+    NSLog(@"{\"name\": \"%@\", \"time\": \"%@\", \"bundleIdentifier\": \"%@\",\"launchDate\": \"%@\",\"PID\": \"%d\", \"isTerminated\": %hhd}", [app localizedName], dateString, [app bundleIdentifier], [app launchDate],[app processIdentifier], [app isTerminated]);
+    }
+
+int main(int argc, const char * argv[]) {
+    @autoreleasepool
+       {
+        NSRunLoop *runLoop = NSRunLoop.currentRunLoop;
+           windowDetector *w = [[windowDetector alloc] init];
+           while ([runLoop runMode:NSDefaultRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:5]]);
+       };
+       return 0;
+
+}
+@end