diff --git a/ParseUI/Classes/Cells/PFCollectionViewCell.h b/ParseUI/Classes/Cells/PFCollectionViewCell.h
index 7760837..d475c43 100644
--- a/ParseUI/Classes/Cells/PFCollectionViewCell.h
+++ b/ParseUI/Classes/Cells/PFCollectionViewCell.h
@@ -21,6 +21,8 @@
 
 #import <UIKit/UIKit.h>
 
+#import <ParseUI/ParseUIConstants.h>
+
 @class PFImageView;
 @class PFObject;
 
@@ -33,14 +35,14 @@
 /*!
  @abstract A simple lazy-loaded label for the collection view cell.
  */
-@property (nonatomic, strong, readonly) UILabel *textLabel;
+@property (nonatomic, strong, readonly, nonnull) UILabel *textLabel;
 
 /*!
  @abstract The lazy-loaded imageView of the collection view cell.
 
  @see PFImageView
  */
-@property (nonatomic, strong, readonly) PFImageView *imageView;
+@property (nonatomic, strong, readonly, nonnull) PFImageView *imageView;
 
 /*!
  @abstract This method should update all the relevant information inside a subclass of `PFCollectionViewCell`.
@@ -50,6 +52,6 @@
 
  @param object An instance of `PFObject` to update from.
  */
-- (void)updateFromObject:(PFObject *)object;
+- (void)updateFromObject:(nullable PFObject *)object;
 
 @end
diff --git a/ParseUI/Classes/Cells/PFPurchaseTableViewCell.h b/ParseUI/Classes/Cells/PFPurchaseTableViewCell.h
index 8c47c7c..d4959bb 100644
--- a/ParseUI/Classes/Cells/PFPurchaseTableViewCell.h
+++ b/ParseUI/Classes/Cells/PFPurchaseTableViewCell.h
@@ -21,6 +21,7 @@
 
 #import <UIKit/UIKit.h>
 
+#import <ParseUI/ParseUIConstants.h>
 #import <ParseUI/PFTableViewCell.h>
 
 /*!
@@ -53,11 +54,11 @@ typedef NS_ENUM(uint8_t, PFPurchaseTableViewCellState) {
 /*!
  @abstract Label where price of the product is displayed.
  */
-@property (nonatomic, strong, readonly) UILabel *priceLabel;
+@property (nonatomic, strong, readonly, nullable) UILabel *priceLabel;
 
 /*!
  @abstract Progress view that is shown, when the product is downloading.
  */
-@property (nonatomic, strong, readonly) UIProgressView *progressView;
+@property (nonatomic, strong, readonly, nullable) UIProgressView *progressView;
 
 @end
diff --git a/ParseUI/Classes/Cells/PFTableViewCell.h b/ParseUI/Classes/Cells/PFTableViewCell.h
index c672bdd..caaccad 100644
--- a/ParseUI/Classes/Cells/PFTableViewCell.h
+++ b/ParseUI/Classes/Cells/PFTableViewCell.h
@@ -21,6 +21,7 @@
 
 #import <UIKit/UIKit.h>
 
+#import <ParseUI/ParseUIConstants.h>
 #import <ParseUI/PFImageView.h>
 
 /*!
@@ -36,6 +37,6 @@
 
  @see PFImageView
  */
-@property (nonatomic, strong, readonly) PFImageView *imageView;
+@property (nonatomic, strong, readonly, nullable) PFImageView *imageView;
 
 @end